MC	<p>1610_1ac0</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_d459</h4><p><canvas id="canvas_b176" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](C(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_d459";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_b176");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Asp-Ile-Val</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 7.3:</p>	+2	Incorrect	+3	Incorrect	+1	Incorrect	-1	Incorrect	0	Correct
MC	<p>9081_d24e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_6961</h4><p><canvas id="canvas_2adc" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCSC)(C(=O)N[C@@H](CO)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_6961";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_2adc");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Met-Ser-Glu-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 1.3:</p>	-2	Incorrect	0	Incorrect	+1	Correct	-1	Incorrect	+2	Incorrect
MC	<p>61e6_18dd</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5099</h4><p><canvas id="canvas_799c" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CC(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5099";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_799c");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ile-Tyr-His-Leu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 9.2:</p>	0	Incorrect	-2	Incorrect	-1	Correct	+1	Incorrect	+2	Incorrect
MC	<p>530b_7e13</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5841</h4><p><canvas id="canvas_1da0" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5841";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_1da0");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-His-Ile-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 5.0:</p>	+3	Incorrect	+1	Incorrect	+4	Incorrect	+2	Correct	+5	Incorrect
MC	<p>afb9_1d52</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_0fe6</h4><p><canvas id="canvas_6386" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_0fe6";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6386");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Thr-Tyr-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 1.7:</p>	+1	Correct	+2	Incorrect	+3	Incorrect	+5	Incorrect	+4	Incorrect
MC	<p>5e9b_a181</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_ce7c</h4><p><canvas id="canvas_55d9" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_ce7c";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_55d9");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Gly-Arg-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 5.0:</p>	-1	Incorrect	+2	Incorrect	+1	Correct	0	Incorrect	+3	Incorrect
MC	<p>80e7_832b</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_79a0</h4><p><canvas id="canvas_37e3" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([H])(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_79a0";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_37e3");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gly-Glu-Met-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 8.1:</p>	-1	Correct	-5	Incorrect	-2	Incorrect	-3	Incorrect	-4	Incorrect
MC	<p>eeea_2b2e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_d91a</h4><p><canvas id="canvas_3863" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_d91a";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3863");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Asn-Ile-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 8.5:</p>	-1	Incorrect	0	Correct	+1	Incorrect	+2	Incorrect	-2	Incorrect
MC	<p>6f91_3efc</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_c104</h4><p><canvas id="canvas_3fea" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCSC)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_c104";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3fea");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Met-Leu-His-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 10.0:</p>	+3	Incorrect	+4	Incorrect	0	Correct	+1	Incorrect	+2	Incorrect
MC	<p>70ce_4e89</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a455</h4><p><canvas id="canvas_3cdc" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a455";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3cdc");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Phe-Ile-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 12.5:</p>	-1	Incorrect	-4	Incorrect	0	Incorrect	-3	Correct	-2	Incorrect
MC	<p>2318_c90a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_70da</h4><p><canvas id="canvas_6111" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CO)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_70da";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6111");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Ser-Gly-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 5.8:</p>	-2	Incorrect	-1	Incorrect	+2	Incorrect	+1	Incorrect	0	Correct
MC	<p>5782_dca4</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_635e</h4><p><canvas id="canvas_be98" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_635e";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_be98");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Leu-His-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 8.7:</p>	+1	Incorrect	-2	Incorrect	0	Correct	-1	Incorrect	+2	Incorrect
MC	<p>f0ed_84b5</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_574e</h4><p><canvas id="canvas_4d02" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)N)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_574e";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_4d02");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asn-Glu-Val-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 2.5:</p>	+3	Incorrect	+1	Correct	0	Incorrect	-1	Incorrect	+2	Incorrect
MC	<p>c659_39ae</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_0e53</h4><p><canvas id="canvas_54aa" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CO)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_0e53";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_54aa");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ser-Phe-His-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 9.9:</p>	-4	Incorrect	-1	Correct	-2	Incorrect	-5	Incorrect	-3	Incorrect
MC	<p>107f_bee3</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1a99</h4><p><canvas id="canvas_2c9d" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1a99";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_2c9d");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Asn-Phe-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 1.1:</p>	0	Incorrect	+3	Incorrect	+2	Correct	+1	Incorrect	+4	Incorrect
MC	<p>5af4_4311</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2967</h4><p><canvas id="canvas_1c8b" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([H])(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CS)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2967";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_1c8b");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gly-Asn-Arg-Cys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 1.5:</p>	+4	Incorrect	+5	Incorrect	+2	Correct	+1	Incorrect	+3	Incorrect
MC	<p>5dc3_1ca0</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_4e90</h4><p><canvas id="canvas_af54" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([H])(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_4e90";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_af54");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gly-Asp-Met-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 2.3:</p>	+1	Incorrect	+2	Incorrect	-1	Incorrect	+3	Incorrect	0	Correct
MC	<p>df30_d0bb</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1a8f</h4><p><canvas id="canvas_5d5c" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CO)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1a8f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_5d5c");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ala-Arg-Cys-Ser</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 7.5:</p>	+1	Correct	-1	Incorrect	0	Incorrect	-2	Incorrect	-3	Incorrect
MC	<p>5c03_c4b1</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1996</h4><p><canvas id="canvas_061d" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1996";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_061d");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Leu-Tyr-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 4.8:</p>	0	Incorrect	-1	Incorrect	+1	Correct	+3	Incorrect	+2	Incorrect
MC	<p>bc03_582f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_08b1</h4><p><canvas id="canvas_36c3" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](C)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_08b1";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_36c3");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Ala-Asn-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 4.6:</p>	+1	Correct	-2	Incorrect	-1	Incorrect	+2	Incorrect	0	Incorrect
MC	<p>e567_5187</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_59e6</h4><p><canvas id="canvas_94b1" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C(C)C)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_59e6";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_94b1");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Val-Cys-His-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 12.3:</p>	-5	Incorrect	-4	Incorrect	-1	Incorrect	-3	Correct	-2	Incorrect
MC	<p>f469_5eba</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_320b</h4><p><canvas id="canvas_8878" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_320b";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_8878");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Lys-Arg-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 5.2:</p>	-2	Incorrect	-1	Incorrect	+1	Correct	+2	Incorrect	0	Incorrect
MC	<p>dc8a_9fbf</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5772</h4><p><canvas id="canvas_04e3" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5772";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_04e3");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Cys-Asp-Gln</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 3.5:</p>	+1	Correct	0	Incorrect	-1	Incorrect	-3	Incorrect	-2	Incorrect
MC	<p>2d74_dd3e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5688</h4><p><canvas id="canvas_45f6" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5688";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_45f6");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Gly-Glu-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 7.6:</p>	0	Incorrect	-3	Incorrect	-1	Correct	+1	Incorrect	-2	Incorrect
MC	<p>14ca_8f8e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_8a17</h4><p><canvas id="canvas_1447" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_8a17";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_1447");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-His-Tyr-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 6.5:</p>	-2	Incorrect	0	Incorrect	-1	Correct	-3	Incorrect	+1	Incorrect
MC	<p>117b_421d</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_09c0</h4><p><canvas id="canvas_560e" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_09c0";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_560e");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ile-Tyr-Asn-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 3.9:</p>	-1	Incorrect	0	Incorrect	-2	Incorrect	+1	Correct	+2	Incorrect
MC	<p>f540_17e0</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_86a5</h4><p><canvas id="canvas_552c" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_86a5";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_552c");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gln-Cys-Arg-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 9.1:</p>	-2	Incorrect	-1	Correct	-4	Incorrect	-5	Incorrect	-3	Incorrect
MC	<p>4a56_2f87</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_d53b</h4><p><canvas id="canvas_8b04" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([H])(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_d53b";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_8b04");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gly-Cys-His-Trp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 12.8:</p>	-4	Incorrect	-3	Incorrect	-1	Incorrect	-5	Incorrect	-2	Correct
MC	<p>be02_d108</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_bc4b</h4><p><canvas id="canvas_fa99" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([H])(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_bc4b";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_fa99");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gly-Lys-Phe-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 11.5:</p>	-1	Correct	0	Incorrect	+3	Incorrect	+2	Incorrect	+1	Incorrect
MC	<p>9ad0_fdd4</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_abde</h4><p><canvas id="canvas_5da7" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_abde";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_5da7");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Ile-Asp-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 9.8:</p>	+1	Incorrect	-2	Incorrect	-3	Incorrect	0	Incorrect	-1	Correct
MC	<p>c2cb_8b49</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_c4a7</h4><p><canvas id="canvas_50c4" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_c4a7";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_50c4");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Ile-Arg-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 2.5:</p>	+4	Incorrect	+2	Incorrect	+3	Incorrect	0	Incorrect	+1	Correct
MC	<p>3b9b_f250</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_73b9</h4><p><canvas id="canvas_a7cb" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_73b9";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_a7cb");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Cys-Glu-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 10.9:</p>	0	Incorrect	-2	Correct	-1	Incorrect	-3	Incorrect	-4	Incorrect
MC	<p>fdaa_7f00</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_e4ea</h4><p><canvas id="canvas_bb07" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_e4ea";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_bb07");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-His-Met-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 6.2:</p>	0	Correct	+3	Incorrect	+4	Incorrect	+1	Incorrect	+2	Incorrect
MC	<p>ec8b_da2f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_621d</h4><p><canvas id="canvas_4672" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCSC)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_621d";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_4672");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Met-Val-Asp-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 3.2:</p>	0	Correct	-1	Incorrect	-2	Incorrect	+2	Incorrect	+1	Incorrect
MC	<p>8f5d_211a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_31d7</h4><p><canvas id="canvas_bf83" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_31d7";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_bf83");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Gly-Asp-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 7.1:</p>	-1	Correct	0	Incorrect	-3	Incorrect	-4	Incorrect	-2	Incorrect
MC	<p>32c3_a178</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_0a9a</h4><p><canvas id="canvas_b003" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_0a9a";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_b003");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Arg-Val-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 4.5:</p>	-3	Incorrect	+1	Incorrect	0	Correct	-1	Incorrect	-2	Incorrect
MC	<p>7a14_869a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_57d5</h4><p><canvas id="canvas_93ce" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_57d5";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_93ce");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Thr-Tyr-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 4.0:</p>	+3	Incorrect	+4	Incorrect	+2	Correct	+1	Incorrect	+5	Incorrect
MC	<p>14fe_8fcf</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1e7f</h4><p><canvas id="canvas_2d87" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1e7f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_2d87");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Met-Glu-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 2.6:</p>	+1	Correct	+2	Incorrect	-1	Incorrect	0	Incorrect	+3	Incorrect
MC	<p>62c4_b6b1</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_8f22</h4><p><canvas id="canvas_defe" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_8f22";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_defe");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Gly-Cys-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 7.4:</p>	+3	Incorrect	0	Correct	+2	Incorrect	-1	Incorrect	+1	Incorrect
MC	<p>7b08_4131</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_d2f1</h4><p><canvas id="canvas_9a18" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CO)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_d2f1";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_9a18");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Thr-Lys-Ser</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 2.1:</p>	+2	Correct	+3	Incorrect	-1	Incorrect	0	Incorrect	+1	Incorrect
MC	<p>8a41_34bf</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_cffe</h4><p><canvas id="canvas_3e94" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCSC)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_cffe";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3e94");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Met-Thr-Lys-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 6.6:</p>	-2	Incorrect	0	Incorrect	-1	Incorrect	+2	Incorrect	+1	Correct
MC	<p>db35_960e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_3293</h4><p><canvas id="canvas_df48" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_3293";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_df48");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Asp-Leu-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 6.6:</p>	+3	Incorrect	+2	Incorrect	+4	Incorrect	+1	Incorrect	0	Correct
MC	<p>c018_c21f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_9585</h4><p><canvas id="canvas_4824" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CC(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_9585";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_4824");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Phe-Cys-Leu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 1.2:</p>	-1	Incorrect	-2	Incorrect	+1	Incorrect	0	Incorrect	+2	Correct
MC	<p>bfd0_dcbf</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_3460</h4><p><canvas id="canvas_eb4e" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_3460";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_eb4e");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>13.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Val-Tyr-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 13.0:</p>	-7	Incorrect	-4	Incorrect	-3	Correct	-5	Incorrect	-6	Incorrect
MC	<p>b09f_a733</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_e241</h4><p><canvas id="canvas_1d64" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C(C)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_e241";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_1d64");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Val-Tyr-Arg-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 12.9:</p>	-3	Correct	-1	Incorrect	-2	Incorrect	-4	Incorrect	0	Incorrect
MC	<p>8920_7c65</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_854a</h4><p><canvas id="canvas_c7ab" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)N)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_854a";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_c7ab");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asn-Tyr-Lys-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 6.5:</p>	+2	Incorrect	0	Incorrect	+3	Incorrect	+4	Incorrect	+1	Correct
MC	<p>8ef5_874b</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_382b</h4><p><canvas id="canvas_36fb" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)N)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_382b";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_36fb");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asn-His-Leu-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 1.4:</p>	+2	Correct	+3	Incorrect	+5	Incorrect	+6	Incorrect	+4	Incorrect
MC	<p>0596_97e1</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_105f</h4><p><canvas id="canvas_cd7a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_105f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_cd7a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Ile-Lys-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 7.4:</p>	+2	Incorrect	+1	Correct	0	Incorrect	-1	Incorrect	+3	Incorrect
MC	<p>fdeb_0e42</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_df28</h4><p><canvas id="canvas_7e4b" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_df28";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_7e4b");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Trp-Tyr-Phe</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 3.4:</p>	-3	Incorrect	-2	Incorrect	+1	Correct	-1	Incorrect	0	Incorrect
MC	<p>2c6e_8c20</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_3f4f</h4><p><canvas id="canvas_241c" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_3f4f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_241c");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ala-Lys-Thr-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 2.1:</p>	-2	Incorrect	+1	Correct	-1	Incorrect	+2	Incorrect	0	Incorrect
MC	<p>cd85_68cf</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_b31f</h4><p><canvas id="canvas_57da" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CS)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_b31f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_57da");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Trp-Asp-Asn-Cys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 1.1:</p>	+3	Incorrect	0	Incorrect	+1	Correct	+2	Incorrect	+4	Incorrect
MC	<p>e101_07be</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_7baf</h4><p><canvas id="canvas_da05" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](C(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_7baf";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_da05");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Phe-Arg-Val</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 11.5:</p>	0	Incorrect	+3	Incorrect	+1	Incorrect	+2	Incorrect	-1	Correct
MC	<p>8751_8f8e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_be81</h4><p><canvas id="canvas_cb41" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C(C)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_be81";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_cb41");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Val-Asp-Tyr-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 8.4:</p>	-2	Incorrect	0	Incorrect	-1	Correct	-3	Incorrect	+1	Incorrect
MC	<p>6658_b355</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_acbc</h4><p><canvas id="canvas_4dcd" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_acbc";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_4dcd");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Trp-Ile-Glu-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 6.6:</p>	+1	Incorrect	+2	Incorrect	+3	Incorrect	+4	Incorrect	0	Correct
MC	<p>eed3_5d8c</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1699</h4><p><canvas id="canvas_579d" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H]([H])(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1699";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_579d");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Gln-Asp-Gly</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 5.2:</p>	-2	Incorrect	0	Incorrect	+2	Incorrect	+1	Incorrect	-1	Correct
MC	<p>a84f_1d93</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_b1a2</h4><p><canvas id="canvas_1d94" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_b1a2";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_1d94");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Asn-Asp-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 2.9:</p>	+2	Incorrect	+1	Correct	-1	Incorrect	0	Incorrect	-2	Incorrect
MC	<p>3eb6_50da</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_34a2</h4><p><canvas id="canvas_24c7" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_34a2";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_24c7");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gln-Cys-Met-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 4.9:</p>	-1	Correct	0	Incorrect	-3	Incorrect	+1	Incorrect	-2	Incorrect
MC	<p>850e_bae2</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_af49</h4><p><canvas id="canvas_e013" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H]([H])(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_af49";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_e013");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Cys-Glu-Gly</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 3.1:</p>	0	Correct	+3	Incorrect	+1	Incorrect	+4	Incorrect	+2	Incorrect
MC	<p>6c7b_9e3a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_8bb6</h4><p><canvas id="canvas_e0da" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CO)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_8bb6";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_e0da");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Cys-Gln-Ser</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 4.3:</p>	+3	Incorrect	+1	Correct	+2	Incorrect	+5	Incorrect	+4	Incorrect
MC	<p>7613_0b1a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_99ab</h4><p><canvas id="canvas_46e7" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_99ab";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_46e7");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>13.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ile-His-Met-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 13.0:</p>	-2	Correct	-6	Incorrect	-4	Incorrect	-5	Incorrect	-3	Incorrect
MC	<p>0bee_4530</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_4482</h4><p><canvas id="canvas_4f0c" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CO)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_4482";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_4f0c");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ser-Lys-Gln-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li></ul><p>Select the net charge at pH 3.7:</p>	+2	Correct	+1	Incorrect	+4	Incorrect	0	Incorrect	+3	Incorrect
MC	<p>6719_1ca0</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_3377</h4><p><canvas id="canvas_7b58" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_3377";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_7b58");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gln-Asp-Cys-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 7.9:</p>	+1	Incorrect	+2	Incorrect	-1	Correct	+3	Incorrect	0	Incorrect
MC	<p>a5cf_b65f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_02c4</h4><p><canvas id="canvas_bb2a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CO)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_02c4";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_bb2a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ser-Asp-Tyr-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 10.4:</p>	-2	Incorrect	-4	Incorrect	0	Incorrect	-1	Incorrect	-3	Correct
MC	<p>27cf_0c16</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_31ae</h4><p><canvas id="canvas_6472" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_31ae";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6472");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-His-Ala-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 6.4:</p>	-2	Incorrect	-1	Incorrect	0	Incorrect	+1	Correct	-3	Incorrect
MC	<p>2937_d7ce</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_c7fd</h4><p><canvas id="canvas_54ec" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CS)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_c7fd";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_54ec");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Met-Asp-Cys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 4.5:</p>	-1	Correct	+2	Incorrect	+3	Incorrect	+1	Incorrect	0	Incorrect
MC	<p>3115_4530</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a85b</h4><p><canvas id="canvas_9416" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a85b";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_9416");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Cys-Tyr-Phe</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 7.5:</p>	+2	Incorrect	+1	Correct	+4	Incorrect	0	Incorrect	+3	Incorrect
MC	<p>534e_347b</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_8cfe</h4><p><canvas id="canvas_1c23" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CO)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_8cfe";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_1c23");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Phe-Lys-Ser</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li></ul><p>Select the net charge at pH 10.8:</p>	+2	Incorrect	+1	Incorrect	-1	Incorrect	+3	Incorrect	0	Correct
MC	<p>1139_9e4a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_6d91</h4><p><canvas id="canvas_8842" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CS)(C(=O)N[C@@H]([C@H](O)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_6d91";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_8842");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Met-Cys-Thr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 2.7:</p>	-1	Incorrect	-2	Incorrect	0	Incorrect	+1	Correct	+2	Incorrect
MC	<p>5bb8_6357</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_35d4</h4><p><canvas id="canvas_dba6" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_35d4";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_dba6");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ile-Cys-Tyr-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 10.8:</p>	0	Incorrect	-1	Incorrect	-3	Correct	+1	Incorrect	-2	Incorrect
MC	<p>d331_52fc</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_f241</h4><p><canvas id="canvas_698a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C(C)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CS)(C(=O)N[C@@H]([H])(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_f241";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_698a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Val-Tyr-Cys-Gly</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 6.4:</p>	0	Correct	-3	Incorrect	-2	Incorrect	-1	Incorrect	+1	Incorrect
MC	<p>af9b_5bd4</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_0554</h4><p><canvas id="canvas_bed0" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H]([H])(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_0554";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_bed0");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Asp-Asn-Gly</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 4.3:</p>	-4	Incorrect	-2	Correct	-5	Incorrect	-1	Incorrect	-3	Incorrect
MC	<p>efdb_cefa</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_972c</h4><p><canvas id="canvas_5bdd" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_972c";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_5bdd");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Asp-Arg-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 7.7:</p>	+1	Incorrect	+2	Incorrect	0	Correct	+4	Incorrect	+3	Incorrect
MC	<p>11b8_b5a8</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_367b</h4><p><canvas id="canvas_edbb" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)N)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_367b";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_edbb");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asn-Gln-Cys-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 10.1:</p>	-3	Incorrect	-5	Incorrect	-2	Correct	-6	Incorrect	-4	Incorrect
MC	<p>0f7e_f9fe</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_6c4a</h4><p><canvas id="canvas_4561" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_6c4a";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_4561");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ala-Glu-Met-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 2.7:</p>	+3	Incorrect	+5	Incorrect	+2	Incorrect	+1	Correct	+4	Incorrect
MC	<p>1c47_e2fb</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_85fb</h4><p><canvas id="canvas_d434" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_85fb";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_d434");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Cys-Gln-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 9.5:</p>	0	Incorrect	-2	Incorrect	-3	Correct	+1	Incorrect	-1	Incorrect
MC	<p>3b7a_6b5a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_3460</h4><p><canvas id="canvas_6955" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_3460";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6955");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Trp-Tyr-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 4.0:</p>	-3	Incorrect	-1	Incorrect	-2	Incorrect	+1	Correct	0	Incorrect
MC	<p>0d44_71c4</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2469</h4><p><canvas id="canvas_23dc" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2469";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_23dc");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Asp-Leu-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 8.1:</p>	+2	Incorrect	+3	Incorrect	0	Incorrect	-1	Correct	+1	Incorrect
MC	<p>bad1_758e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2bbb</h4><p><canvas id="canvas_9cfe" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](C(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2bbb";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_9cfe");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Arg-Phe-Val</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 4.5:</p>	+2	Incorrect	-1	Incorrect	+1	Correct	0	Incorrect	+3	Incorrect
MC	<p>6c67_5080</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_6f65</h4><p><canvas id="canvas_d984" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_6f65";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_d984");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Ala-Arg-Leu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 7.1:</p>	+4	Incorrect	+1	Incorrect	+2	Incorrect	+3	Incorrect	0	Correct
MC	<p>d729_6cbc</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_f7bd</h4><p><canvas id="canvas_3d82" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_f7bd";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3d82");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Val-Glu-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 3.3:</p>	+4	Incorrect	+1	Correct	+5	Incorrect	+2	Incorrect	+3	Incorrect
MC	<p>9339_8f8e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_3daa</h4><p><canvas id="canvas_9ac8" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CO)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_3daa";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_9ac8");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Ser-Val-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 4.9:</p>	-2	Incorrect	0	Incorrect	-1	Correct	-3	Incorrect	+1	Incorrect
MC	<p>0198_92cc</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_0b92</h4><p><canvas id="canvas_ed9e" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_0b92";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_ed9e");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Ile-Met-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 6.0:</p>	+3	Incorrect	0	Incorrect	+1	Incorrect	+2	Incorrect	-1	Correct
MC	<p>223b_a57e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_d428</h4><p><canvas id="canvas_9c7d" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C(C)C)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_d428";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_9c7d");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Val-Met-Lys-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 7.4:</p>	0	Correct	+2	Incorrect	+1	Incorrect	-2	Incorrect	-1	Incorrect
MC	<p>2619_acc1</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_46ec</h4><p><canvas id="canvas_54f5" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](CO)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_46ec";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_54f5");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Ser-Asn-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 10.6:</p>	-2	Incorrect	-3	Correct	-1	Incorrect	-4	Incorrect	0	Incorrect
MC	<p>adbc_8c99</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_0101</h4><p><canvas id="canvas_54c7" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_0101";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_54c7");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Trp-Glu-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 11.3:</p>	-1	Incorrect	-3	Incorrect	-2	Correct	0	Incorrect	-4	Incorrect
MC	<p>cf7b_874c</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_f8d5</h4><p><canvas id="canvas_a1d1" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CO)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_f8d5";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_a1d1");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ser-Arg-Ala-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 3.9:</p>	+4	Incorrect	+2	Incorrect	+3	Incorrect	+1	Correct	+5	Incorrect
MC	<p>c2eb_b666</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_c8a1</h4><p><canvas id="canvas_152a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CO)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_c8a1";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_152a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Tyr-Trp-Ser</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 2.5:</p>	-2	Incorrect	-3	Incorrect	+1	Incorrect	0	Correct	-1	Incorrect
MC	<p>2265_522c</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2478</h4><p><canvas id="canvas_3d40" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2478";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3d40");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Cys-Met-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 1.2:</p>	+2	Correct	0	Incorrect	-2	Incorrect	+1	Incorrect	-1	Incorrect
MC	<p>b6db_16ee</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_faff</h4><p><canvas id="canvas_c611" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_faff";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_c611");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Lys-Val-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 12.6:</p>	-1	Correct	-3	Incorrect	-4	Incorrect	-5	Incorrect	-2	Incorrect
MC	<p>e550_ac82</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_b489</h4><p><canvas id="canvas_8f82" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_b489";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_8f82");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Trp-Tyr-Leu-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 9.4:</p>	-2	Correct	-5	Incorrect	-6	Incorrect	-4	Incorrect	-3	Incorrect
MC	<p>edeb_db49</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_db13</h4><p><canvas id="canvas_96c6" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_db13";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_96c6");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Gln-Cys-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 7.1:</p>	+4	Incorrect	+3	Incorrect	+1	Incorrect	0	Correct	+2	Incorrect
MC	<p>fca9_db52</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_ae54</h4><p><canvas id="canvas_eb68" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_ae54";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_eb68");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gln-Asp-Phe-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 11.6:</p>	0	Incorrect	-2	Incorrect	-4	Incorrect	-3	Correct	-1	Incorrect
MC	<p>e325_1b1b</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_b878</h4><p><canvas id="canvas_dafa" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](C(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_b878";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_dafa");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Tyr-Ile-Val</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 10.4:</p>	-5	Incorrect	-2	Incorrect	-4	Incorrect	-3	Correct	-6	Incorrect
MC	<p>0465_5fed</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_df20</h4><p><canvas id="canvas_7d7a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_df20";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_7d7a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Arg-Asn-Trp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 1.3:</p>	+6	Incorrect	+3	Correct	+5	Incorrect	+4	Incorrect	+7	Incorrect
MC	<p>c50d_29dd</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_e562</h4><p><canvas id="canvas_9582" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CO)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_e562";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_9582");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Asp-Ser-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 8.6:</p>	-3	Incorrect	-1	Incorrect	0	Correct	-2	Incorrect	-4	Incorrect
MC	<p>6e50_550d</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_76d4</h4><p><canvas id="canvas_015d" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_76d4";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_015d");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Cys-Lys-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 10.1:</p>	-1	Incorrect	-2	Correct	0	Incorrect	-4	Incorrect	-3	Incorrect
MC	<p>6a2f_1c50</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_edb3</h4><p><canvas id="canvas_8e43" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCSC)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_edb3";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_8e43");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Met-Thr-Asp-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 10.5:</p>	-5	Incorrect	-3	Incorrect	-1	Incorrect	-4	Incorrect	-2	Correct
MC	<p>16d3_0a83</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_c1c3</h4><p><canvas id="canvas_d2e3" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](C(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_c1c3";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_d2e3");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Tyr-His-Val</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 9.4:</p>	-1	Correct	+2	Incorrect	+3	Incorrect	0	Incorrect	+1	Incorrect
MC	<p>8e2b_fdbd</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_9f25</h4><p><canvas id="canvas_3598" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_9f25";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3598");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Asn-Asp-Phe</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 6.1:</p>	0	Correct	+3	Incorrect	+1	Incorrect	+2	Incorrect	+4	Incorrect
MC	<p>66ad_30fe</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_f693</h4><p><canvas id="canvas_817f" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_f693";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_817f");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Trp-Lys-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 4.7:</p>	-1	Incorrect	+2	Correct	0	Incorrect	+3	Incorrect	+1	Incorrect
MC	<p>3a5d_ddb1</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1e30</h4><p><canvas id="canvas_955d" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1e30";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_955d");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Glu-Tyr-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 12.0:</p>	-4	Correct	-6	Incorrect	-3	Incorrect	-5	Incorrect	-7	Incorrect
MC	<p>7be9_f887</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2779</h4><p><canvas id="canvas_2de9" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCSC)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2779";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_2de9");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Met-Asp-Leu-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 4.3:</p>	+4	Incorrect	+3	Incorrect	+2	Incorrect	+1	Incorrect	0	Correct
MC	<p>1986_a2e4</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5d8d</h4><p><canvas id="canvas_ef75" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5d8d";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_ef75");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Met-Ala-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 8.1:</p>	+3	Incorrect	+2	Incorrect	+1	Incorrect	0	Correct	-1	Incorrect
MC	<p>e42f_ec51</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_ef58</h4><p><canvas id="canvas_00f6" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_ef58";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_00f6");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Thr-Asp-Trp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 3.6:</p>	+1	Incorrect	-2	Incorrect	-1	Incorrect	0	Correct	+2	Incorrect
MC	<p>1d0b_fc40</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_66c6</h4><p><canvas id="canvas_d845" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCSC)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_66c6";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_d845");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Met-Lys-His-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 2.0:</p>	+3	Correct	+2	Incorrect	+5	Incorrect	+1	Incorrect	+4	Incorrect
MC	<p>eeb7_fd4a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_7816</h4><p><canvas id="canvas_bd13" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_7816";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_bd13");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-His-Met-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 1.2:</p>	+3	Incorrect	+4	Incorrect	+6	Incorrect	+5	Incorrect	+2	Correct
MC	<p>41ff_b691</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_4ebe</h4><p><canvas id="canvas_ef27" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_4ebe";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_ef27");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Trp-Gln-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 2.1:</p>	-2	Incorrect	-1	Incorrect	0	Incorrect	+1	Correct	+2	Incorrect
MC	<p>d10b_9bb9</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_9908</h4><p><canvas id="canvas_8e16" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_9908";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_8e16");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Glu-Ile-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 4.6:</p>	+1	Incorrect	+2	Incorrect	-2	Incorrect	-1	Incorrect	0	Correct
MC	<p>ec31_908d</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_4b9e</h4><p><canvas id="canvas_f834" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_4b9e";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_f834");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Phe-Cys-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 7.5:</p>	-3	Incorrect	-6	Incorrect	-5	Incorrect	-4	Incorrect	-2	Correct
MC	<p>8e40_95fe</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_591a</h4><p><canvas id="canvas_5587" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_591a";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_5587");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ala-Tyr-Leu-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 10.2:</p>	-3	Incorrect	-4	Incorrect	-1	Incorrect	0	Incorrect	-2	Correct
MC	<p>d038_a5e3</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_df87</h4><p><canvas id="canvas_ba3c" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C(C)C)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_df87";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_ba3c");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Val-Phe-Cys-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 2.7:</p>	-2	Incorrect	0	Incorrect	+1	Correct	-3	Incorrect	-1	Incorrect
MC	<p>8a4e_7dd6</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_ce4e</h4><p><canvas id="canvas_e34f" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_ce4e";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_e34f");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Phe-Asn-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 6.1:</p>	-2	Incorrect	-1	Incorrect	0	Correct	-4	Incorrect	-3	Incorrect
MC	<p>25cc_5d95</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_b275</h4><p><canvas id="canvas_1436" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CC(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_b275";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_1436");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Phe-Glu-His-Leu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 6.8:</p>	-4	Incorrect	-5	Incorrect	-3	Incorrect	-2	Incorrect	-1	Correct
MC	<p>6b17_7ab7</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_fbe1</h4><p><canvas id="canvas_a21c" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C(C)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_fbe1";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_a21c");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Val-Arg-Asp-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 7.9:</p>	-1	Incorrect	0	Correct	+3	Incorrect	+1	Incorrect	+2	Incorrect
MC	<p>f10f_24b0</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_b974</h4><p><canvas id="canvas_f30b" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_b974";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_f30b");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Trp-Glu-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 9.8:</p>	-4	Incorrect	-3	Incorrect	-5	Incorrect	-1	Incorrect	-2	Correct
MC	<p>f719_4b4c</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1e90</h4><p><canvas id="canvas_e24a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1e90";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_e24a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Gly-Asn-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 1.2:</p>	-1	Incorrect	+1	Incorrect	0	Incorrect	+2	Correct	+3	Incorrect
MC	<p>e831_db52</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a625</h4><p><canvas id="canvas_0055" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a625";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_0055");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Val-Phe-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 5.2:</p>	0	Incorrect	-2	Incorrect	-4	Incorrect	-3	Incorrect	-1	Correct
MC	<p>7fa7_d2a4</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2062</h4><p><canvas id="canvas_20e4" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2062";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_20e4");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Phe-Val-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 6.3:</p>	+3	Incorrect	-1	Incorrect	+1	Incorrect	+2	Incorrect	0	Correct
MC	<p>af34_7f9e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_72bb</h4><p><canvas id="canvas_e4ce" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_72bb";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_e4ce");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Phe-Glu-Ile-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 1.4:</p>	+4	Incorrect	+5	Incorrect	+6	Incorrect	+3	Incorrect	+2	Correct
MC	<p>3aeb_39cb</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5f5d</h4><p><canvas id="canvas_6ff0" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CO)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5f5d";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6ff0");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ser-Leu-Lys-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 2.2:</p>	+4	Incorrect	+3	Incorrect	+5	Incorrect	+1	Correct	+2	Incorrect
MC	<p>2a01_f575</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_57d9</h4><p><canvas id="canvas_dba4" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCSC)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_57d9";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_dba4");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Met-Lys-Trp-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li></ul><p>Select the net charge at pH 7.4:</p>	+3	Incorrect	+1	Incorrect	0	Incorrect	+4	Incorrect	+2	Correct
MC	<p>e25c_73a5</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_4d12</h4><p><canvas id="canvas_90a3" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_4d12";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_90a3");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Asp-Val-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 4.8:</p>	-3	Incorrect	-2	Incorrect	0	Correct	-4	Incorrect	-1	Incorrect
MC	<p>00b7_1a2f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_fb4a</h4><p><canvas id="canvas_f8ec" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_fb4a";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_f8ec");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Gly-Lys-Trp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li></ul><p>Select the net charge at pH 4.0:</p>	+5	Incorrect	+4	Incorrect	+3	Incorrect	+2	Correct	+6	Incorrect
MC	<p>9807_e9a2</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1748</h4><p><canvas id="canvas_f252" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](C)(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1748";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_f252");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Tyr-Ala-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 1.3:</p>	-1	Incorrect	0	Incorrect	-2	Incorrect	+2	Correct	+1	Incorrect
MC	<p>dc17_522c</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_c19e</h4><p><canvas id="canvas_e975" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_c19e";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_e975");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Lys-Thr-Gln</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 8.9:</p>	+2	Incorrect	0	Correct	-2	Incorrect	+1	Incorrect	-1	Incorrect
MC	<p>00ab_ac13</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_704d</h4><p><canvas id="canvas_d7f4" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_704d";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_d7f4");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Leu-Asp-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 4.2:</p>	+4	Incorrect	+1	Incorrect	0	Correct	+3	Incorrect	+2	Incorrect
MC	<p>e83b_fb7d</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_882f</h4><p><canvas id="canvas_3473" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_882f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3473");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Lys-Asn-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 4.2:</p>	+4	Incorrect	0	Correct	+3	Incorrect	+1	Incorrect	+2	Incorrect
MC	<p>0b32_441f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_220c</h4><p><canvas id="canvas_7c82" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_220c";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_7c82");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ile-Arg-Trp-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 6.6:</p>	0	Correct	-3	Incorrect	-2	Incorrect	-4	Incorrect	-1	Incorrect
MC	<p>b0fd_9019</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_3ee4</h4><p><canvas id="canvas_16ea" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_3ee4";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_16ea");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Asn-Tyr-Phe</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 7.4:</p>	+1	Incorrect	0	Incorrect	+2	Incorrect	-1	Correct	+3	Incorrect
MC	<p>5c16_b0b1</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1cc7</h4><p><canvas id="canvas_6079" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1cc7";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6079");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Tyr-Trp-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 3.6:</p>	+2	Incorrect	+3	Incorrect	+1	Incorrect	0	Correct	+4	Incorrect
MC	<p>bce0_cd4e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a9c4</h4><p><canvas id="canvas_343c" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CC(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a9c4";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_343c");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Glu-Gln-Leu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 1.9:</p>	0	Incorrect	+2	Correct	+4	Incorrect	+3	Incorrect	+1	Incorrect
MC	<p>0c0f_59fd</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_0e99</h4><p><canvas id="canvas_b295" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_0e99";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_b295");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Asp-Tyr-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 5.7:</p>	-3	Incorrect	-4	Incorrect	-5	Incorrect	-2	Correct	-1	Incorrect
MC	<p>cb28_41cd</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2af8</h4><p><canvas id="canvas_4b33" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2af8";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_4b33");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Val-Phe-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li></ul><p>Select the net charge at pH 8.1:</p>	+3	Incorrect	0	Incorrect	+4	Incorrect	+2	Correct	+1	Incorrect
MC	<p>675e_b134</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_65c6</h4><p><canvas id="canvas_73ef" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_65c6";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_73ef");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ala-Ile-His-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 2.5:</p>	+4	Incorrect	+2	Correct	0	Incorrect	+3	Incorrect	+1	Incorrect
MC	<p>fe4f_a392</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_3ce5</h4><p><canvas id="canvas_97f8" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_3ce5";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_97f8");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Val-Thr-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 11.1:</p>	0	Incorrect	-1	Correct	+1	Incorrect	-3	Incorrect	-2	Incorrect
MC	<p>fd99_5eba</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a2c2</h4><p><canvas id="canvas_c575" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a2c2";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_c575");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Gln-Asp-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 10.2:</p>	-2	Incorrect	-1	Incorrect	+1	Incorrect	+2	Incorrect	0	Correct
MC	<p>c9ab_4de1</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_d214</h4><p><canvas id="canvas_cfd0" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_d214";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_cfd0");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Met-Tyr-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 9.8:</p>	0	Incorrect	+1	Incorrect	-2	Correct	-1	Incorrect	+2	Incorrect
MC	<p>af6d_4dc4</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2bf7</h4><p><canvas id="canvas_17c4" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H]([H])(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2bf7";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_17c4");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gln-Asp-Lys-Gly</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 2.8:</p>	+2	Incorrect	+1	Correct	+4	Incorrect	+3	Incorrect	+5	Incorrect
MC	<p>071c_cc6f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_ae28</h4><p><canvas id="canvas_baa6" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_ae28";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_baa6");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Ile-Gly-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 8.0:</p>	+1	Correct	0	Incorrect	-2	Incorrect	+2	Incorrect	-1	Incorrect
MC	<p>7648_5c3c</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_4f11</h4><p><canvas id="canvas_b969" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_4f11";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_b969");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Tyr-Gly-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 5.5:</p>	+2	Incorrect	0	Correct	+1	Incorrect	-2	Incorrect	-1	Incorrect
MC	<p>9c05_7ab7</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_035e</h4><p><canvas id="canvas_07de" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_035e";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_07de");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Arg-Gly-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 9.4:</p>	-1	Correct	0	Incorrect	+3	Incorrect	+1	Incorrect	+2	Incorrect
MC	<p>334b_7b75</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_0763</h4><p><canvas id="canvas_a240" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](CC(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_0763";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_a240");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Asp-Val-Leu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 4.8:</p>	-2	Incorrect	-4	Incorrect	0	Correct	-3	Incorrect	-1	Incorrect
MC	<p>b377_2579</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a8fc</h4><p><canvas id="canvas_7961" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a8fc";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_7961");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ala-Lys-His-Ile</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 10.3:</p>	-2	Incorrect	+2	Incorrect	-1	Incorrect	0	Correct	+1	Incorrect
MC	<p>3997_05bd</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_c5fd</h4><p><canvas id="canvas_1340" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_c5fd";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_1340");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Gln-His-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 4.2:</p>	+1	Incorrect	+2	Correct	0	Incorrect	-1	Incorrect	-2	Incorrect
MC	<p>1a85_742a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1b3f</h4><p><canvas id="canvas_9af8" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1b3f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_9af8");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Arg-Thr-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li></ul><p>Select the net charge at pH 12.5:</p>	+3	Incorrect	+2	Incorrect	-1	Correct	+1	Incorrect	0	Incorrect
MC	<p>dcb4_0265</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_83f8</h4><p><canvas id="canvas_cf44" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_83f8";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_cf44");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Asp-Leu-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 7.2:</p>	-3	Incorrect	-2	Incorrect	0	Incorrect	+1	Correct	-1	Incorrect
MC	<p>afec_758d</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_379c</h4><p><canvas id="canvas_157a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_379c";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_157a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Arg-Ala-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 8.4:</p>	-2	Incorrect	0	Correct	-1	Incorrect	-3	Incorrect	-4	Incorrect
MC	<p>af22_e81c</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1d44</h4><p><canvas id="canvas_6719" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CO)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1d44";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6719");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Arg-Ser-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 4.6:</p>	+2	Correct	+5	Incorrect	+3	Incorrect	+4	Incorrect	+1	Incorrect
MC	<p>189c_d2fe</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_f2f7</h4><p><canvas id="canvas_daa0" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](C)(C(=O)N[C@@H](CCC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_f2f7";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_daa0");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Glu-Ala-Gln</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 6.3:</p>	0	Correct	+4	Incorrect	+2	Incorrect	+1	Incorrect	+3	Incorrect
MC	<p>736b_918d</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_efdf</h4><p><canvas id="canvas_b17b" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_efdf";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_b17b");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Trp-Tyr-Glu-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 9.2:</p>	-3	Incorrect	+1	Incorrect	-1	Correct	0	Incorrect	-2	Incorrect
MC	<p>b8a7_ba74</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5331</h4><p><canvas id="canvas_b5fd" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CO)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H]([H])(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5331";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_b5fd");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ser-Cys-Asp-Gly</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 4.8:</p>	+1	Incorrect	0	Incorrect	-2	Incorrect	-1	Correct	-3	Incorrect
MC	<p>6f21_8f0f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_f9c9</h4><p><canvas id="canvas_52c7" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CS)(C(=O)N[C@@H]([C@H](O)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_f9c9";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_52c7");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Gln-Cys-Thr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 9.1:</p>	-4	Incorrect	-3	Correct	-5	Incorrect	-2	Incorrect	-1	Incorrect
MC	<p>f3be_78e0</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5ce4</h4><p><canvas id="canvas_b760" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5ce4";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_b760");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gln-Arg-Val-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 12.7:</p>	-4	Incorrect	0	Incorrect	-1	Incorrect	-2	Correct	-3	Incorrect
MC	<p>9f92_4dc4</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_3b3a</h4><p><canvas id="canvas_846e" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)N)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](C)(C(=O)N[C@@H](CCCCN)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_3b3a";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_846e");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asn-Arg-Ala-Lys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li></ul><p>Select the net charge at pH 6.6:</p>	+2	Correct	+1	Incorrect	+4	Incorrect	+3	Incorrect	+5	Incorrect
MC	<p>315b_2bb3</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_f6f8</h4><p><canvas id="canvas_e303" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCSC)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_f6f8";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_e303");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Met-Cys-Asn-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 10.5:</p>	-5	Incorrect	-1	Incorrect	-2	Incorrect	-3	Correct	-4	Incorrect
MC	<p>daa3_95ec</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a7b2</h4><p><canvas id="canvas_bc6a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CCC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a7b2";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_bc6a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Gly-Lys-Gln</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 12.3:</p>	-1	Incorrect	-4	Incorrect	-5	Incorrect	-3	Incorrect	-2	Correct
MC	<p>1264_7b98</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_cf8b</h4><p><canvas id="canvas_632b" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_cf8b";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_632b");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Trp-Arg-Leu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 1.1:</p>	+2	Correct	+4	Incorrect	+3	Incorrect	+1	Incorrect	+5	Incorrect
MC	<p>ff8c_d14a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2b84</h4><p><canvas id="canvas_5a04" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H]([C@H](O)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2b84";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_5a04");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Asp-Lys-Thr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 3.8:</p>	-1	Incorrect	+1	Incorrect	+2	Incorrect	+3	Incorrect	0	Correct
MC	<p>52a7_0470</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_4881</h4><p><canvas id="canvas_11c8" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_4881";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_11c8");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Asp-Leu-Trp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 11.4:</p>	-4	Incorrect	-5	Incorrect	-6	Incorrect	-2	Correct	-3	Incorrect
MC	<p>e818_2247</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_26e9</h4><p><canvas id="canvas_ebed" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_26e9";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_ebed");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Ala-Lys-Phe</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 3.2:</p>	-1	Incorrect	+2	Incorrect	+1	Correct	-2	Incorrect	0	Incorrect
MC	<p>34e6_71c7</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_eb4c</h4><p><canvas id="canvas_af94" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CO)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_eb4c";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_af94");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ala-Asp-Cys-Ser</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 6.5:</p>	-4	Incorrect	-1	Correct	-5	Incorrect	-2	Incorrect	-3	Incorrect
MC	<p>5ac3_eac4</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2ad0</h4><p><canvas id="canvas_7771" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CO)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2ad0";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_7771");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Asp-Ser-Phe</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 11.4:</p>	-2	Incorrect	-1	Correct	+1	Incorrect	0	Incorrect	+2	Incorrect
MC	<p>fa16_940c</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_ecc5</h4><p><canvas id="canvas_c18e" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_ecc5";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_c18e");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ala-His-Leu-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 10.8:</p>	-2	Correct	-5	Incorrect	-1	Incorrect	-3	Incorrect	-4	Incorrect
MC	<p>7a7c_1533</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_4c1f</h4><p><canvas id="canvas_2686" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](C(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_4c1f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_2686");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Arg-Gly-Val</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 7.4:</p>	+1	Incorrect	+2	Incorrect	0	Correct	+3	Incorrect	-1	Incorrect
MC	<p>e20b_d2ad</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_69e1</h4><p><canvas id="canvas_36a5" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](CS)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_69e1";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_36a5");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Lys-Asn-Cys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 10.8:</p>	0	Incorrect	+1	Incorrect	-1	Incorrect	-3	Correct	-2	Incorrect
MC	<p>2b18_6ca2</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1f2a</h4><p><canvas id="canvas_97c3" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1f2a";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_97c3");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Trp-Gly-Arg-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 11.3:</p>	0	Incorrect	-4	Incorrect	-3	Incorrect	-1	Correct	-2	Incorrect
MC	<p>bfbd_5afe</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1330</h4><p><canvas id="canvas_3cc6" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1330";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3cc6");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>6.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ala-His-Ile-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 6.2:</p>	0	Incorrect	-1	Correct	-4	Incorrect	-3	Incorrect	-2	Incorrect
MC	<p>0486_204b</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_9545</h4><p><canvas id="canvas_453e" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_9545";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_453e");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Phe-Asp-Tyr-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 3.3:</p>	+4	Incorrect	+2	Incorrect	+1	Incorrect	0	Correct	+3	Incorrect
MC	<p>94ea_f8a2</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_9557</h4><p><canvas id="canvas_6846" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CS)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CO)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_9557";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6846");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Phe-Cys-Glu-Ser</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 1.3:</p>	-1	Incorrect	+1	Correct	+2	Incorrect	0	Incorrect	-2	Incorrect
MC	<p>3f2c_b22a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_b49d</h4><p><canvas id="canvas_bc53" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_b49d";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_bc53");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Leu-Lys-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 5.6:</p>	+3	Incorrect	+1	Incorrect	0	Correct	+2	Incorrect	+4	Incorrect
MC	<p>6cbf_6ca2</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_f839</h4><p><canvas id="canvas_6cb8" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(C)C)(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_f839";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6cb8");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Leu-Asp-Lys-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 7.7:</p>	0	Correct	-4	Incorrect	-3	Incorrect	-1	Incorrect	-2	Incorrect
MC	<p>3ead_05bd</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_696f</h4><p><canvas id="canvas_0e22" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_696f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_0e22");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Glu-Ile-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 7.8:</p>	+1	Incorrect	+2	Incorrect	0	Correct	-1	Incorrect	-2	Incorrect
MC	<p>dff7_aff2</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_8b31</h4><p><canvas id="canvas_0e0f" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_8b31";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_0e0f");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Arg-Leu-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 9.2:</p>	-3	Incorrect	0	Incorrect	-2	Incorrect	-4	Incorrect	-1	Correct
MC	<p>f036_004a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a62b</h4><p><canvas id="canvas_318b" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCSC)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a62b";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_318b");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Gln-His-Met</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 3.0:</p>	+2	Incorrect	0	Incorrect	-1	Incorrect	+1	Correct	+3	Incorrect
MC	<p>325e_b691</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_f8cc</h4><p><canvas id="canvas_c84d" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_f8cc";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_c84d");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Met-Lys-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 3.4:</p>	-2	Incorrect	-1	Incorrect	0	Incorrect	+1	Incorrect	+2	Correct
MC	<p>da12_9495</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_7cbb</h4><p><canvas id="canvas_6908" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([H])(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H]([C@H](O)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_7cbb";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_6908");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>5.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gly-Lys-Tyr-Thr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 5.8:</p>	+1	Correct	-3	Incorrect	-1	Incorrect	-2	Incorrect	0	Incorrect
MC	<p>3b58_ea33</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_d770</h4><p><canvas id="canvas_a468" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H]([H])(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_d770";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_a468");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.3</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Arg-Met-Gly</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 4.3:</p>	-2	Incorrect	-3	Incorrect	0	Correct	+1	Incorrect	-1	Incorrect
MC	<p>6c9e_dfcf</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_e955</h4><p><canvas id="canvas_c534" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)N)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CS)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_e955";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_c534");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asn-Phe-Glu-Cys</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 10.9:</p>	-1	Incorrect	-3	Correct	0	Incorrect	+1	Incorrect	-2	Incorrect
MC	<p>2cca_d39a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a9dd</h4><p><canvas id="canvas_2a69" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a9dd";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_2a69");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Val-Glu-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 12.2:</p>	0	Incorrect	-2	Incorrect	-1	Incorrect	-4	Incorrect	-3	Correct
MC	<p>fbdc_e6e1</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_26a3</h4><p><canvas id="canvas_a3b5" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CO)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_26a3";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_a3b5");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-Lys-Ser-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 11.7:</p>	+2	Incorrect	-1	Correct	+1	Incorrect	+3	Incorrect	0	Incorrect
MC	<p>d3af_61be</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_2f03</h4><p><canvas id="canvas_9d42" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](CO)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_2f03";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_9d42");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>12.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Ser-Phe-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Cys side chain: 8.3</li></ul><p>Select the net charge at pH 12.8:</p>	-1	Incorrect	-3	Incorrect	-4	Incorrect	0	Incorrect	-2	Correct
MC	<p>0f6a_aff2</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_bd3d</h4><p><canvas id="canvas_3e4a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H]([H])(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_bd3d";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_3e4a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Gly-Leu-His</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 7.5:</p>	-3	Incorrect	0	Incorrect	-2	Incorrect	-4	Incorrect	-1	Correct
MC	<p>c938_4476</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_7f95</h4><p><canvas id="canvas_d0f2" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CS)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_7f95";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_d0f2");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>10.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Cys-Glu-Ile-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Glu side chain: 4.1</li><li>Cys side chain: 8.3</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 10.6:</p>	-8	Incorrect	-6	Incorrect	-7	Incorrect	-4	Correct	-5	Incorrect
MC	<p>803c_0d1f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a138</h4><p><canvas id="canvas_de01" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](C(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a138";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_de01");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Arg-His-Ile-Val</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 7.9:</p>	+1	Correct	-1	Incorrect	0	Incorrect	+2	Incorrect	-2	Incorrect
MC	<p>103d_d653</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5281</h4><p><canvas id="canvas_b901" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CCC(=O)N)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5281";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_b901");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Tyr-Arg-Gln-Ile</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 3.1:</p>	+3	Incorrect	+1	Correct	+5	Incorrect	+2	Incorrect	+4	Incorrect
MC	<p>38e6_29db</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_bfdc</h4><p><canvas id="canvas_fbea" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](C(C)C)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_bfdc";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_fbea");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.9</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">His-Val-Glu-Gln</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 7.9:</p>	-2	Incorrect	+1	Incorrect	-3	Incorrect	0	Incorrect	-1	Correct
MC	<p>9607_5357</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_a5ef</h4><p><canvas id="canvas_2d68" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([H])(C(=O)N[C@@H](CC(=O)O)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC(=O)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_a5ef";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_2d68");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Gly-Asp-Glu-Asn</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 8.4:</p>	+1	Incorrect	-3	Incorrect	-2	Correct	0	Incorrect	-1	Incorrect
MC	<p>d73e_57e7</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_28c0</h4><p><canvas id="canvas_a903" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCSC)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_28c0";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_a903");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.1</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ile-His-Met-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 11.1:</p>	+2	Incorrect	+1	Incorrect	+3	Incorrect	-1	Incorrect	0	Correct
MC	<p>0146_d935</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_da69</h4><p><canvas id="canvas_36c0" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CC(=O)N)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_da69";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_36c0");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.5</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Asn-Tyr-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 9.5:</p>	-2	Incorrect	-1	Correct	-5	Incorrect	-4	Incorrect	-3	Incorrect
MC	<p>7680_d24e</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_595b</h4><p><canvas id="canvas_47aa" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_595b";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_47aa");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>3.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ile-His-Arg-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 3.2:</p>	-2	Incorrect	0	Incorrect	+1	Incorrect	-1	Incorrect	+2	Correct
MC	<p>f016_9495</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_c224</h4><p><canvas id="canvas_f3c3" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H]([C@H](CC)C)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_c224";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_f3c3");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Ile-His-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>His side chain: 6.0</li></ul><p>Select the net charge at pH 11.8:</p>	+1	Incorrect	-3	Incorrect	-1	Incorrect	-2	Incorrect	0	Correct
MC	<p>c026_34bf</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_0e62</h4><p><canvas id="canvas_7e9a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_0e62";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_7e9a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>8.0</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Thr-Lys-Trp-Tyr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 8.0:</p>	-2	Incorrect	0	Incorrect	-1	Incorrect	+2	Incorrect	+1	Correct
MC	<p>e6a0_4140</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_1b3f</h4><p><canvas id="canvas_bec6" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](CO)(C(=O)N[C@@H]([C@H](O)C)(C(=O)N[C@@H](CCCNC(=N)N)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_1b3f";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_bec6");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>9.7</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Ser-Thr-Arg</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Arg side chain: 12.5</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 9.7:</p>	+3	Incorrect	+1	Incorrect	+2	Incorrect	0	Incorrect	-1	Correct
MC	<p>e0ef_4c14</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_b664</h4><p><canvas id="canvas_50f2" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CCC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_b664";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_50f2");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-Trp-Lys-Glu</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Asp side chain: 3.7</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 4.8:</p>	-3	Incorrect	-1	Correct	-2	Incorrect	0	Incorrect	-4	Incorrect
MC	<p>3a81_29ed</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_b629</h4><p><canvas id="canvas_fffe" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CO)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_b629";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_fffe");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>2.8</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Ser-His-Tyr-Ala</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 2.8:</p>	+1	Correct	+4	Incorrect	+2	Incorrect	+3	Incorrect	0	Incorrect
MC	<p>ed75_493a</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_5d36</h4><p><canvas id="canvas_e67a" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CCCCN)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_5d36";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_e67a");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>1.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Glu-Lys-Leu-Trp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 1.6:</p>	0	Incorrect	-1	Incorrect	+3	Incorrect	+1	Incorrect	+2	Correct
MC	<p>5447_0ac7</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_d40e</h4><p><canvas id="canvas_f4ab" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CCCCN)(C(=O)N[C@@H](CCC(=O)O)(C(=O)N[C@@H](CC(C)C)(C(=O)N[C@@H]([C@H](O)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_d40e";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_f4ab");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>4.4</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Lys-Glu-Leu-Thr</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Lys side chain: 10.5</li><li>Glu side chain: 4.1</li></ul><p>Select the net charge at pH 4.4:</p>	-3	Incorrect	+1	Incorrect	0	Correct	-2	Incorrect	-1	Incorrect
MC	<p>b3ee_b65f</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_14af</h4><p><canvas id="canvas_808c" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC(=O)O)(C(=O)N[C@@H](CC1=C[NH]C=N1)(C(=O)N[C@@H](C)(C(=O)N[C@@H](C(C)C)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_14af";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_808c");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>11.6</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Asp-His-Ala-Val</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>His side chain: 6.0</li><li>Asp side chain: 3.7</li></ul><p>Select the net charge at pH 11.6:</p>	-2	Correct	-4	Incorrect	0	Incorrect	-1	Incorrect	-3	Incorrect
MC	<p>e0f8_e310</p> <script src="https://unpkg.com/@rdkit/rdkit/dist/RDKit_minimal.js"></script><h4>tetrapeptide_4b63</h4><p><canvas id="canvas_b607" width="540" height="320"></canvas></p><hr/><script>/* */initRDKitModule().then(function(instance){RDKitModule=instance;console.log("RDKit:"+RDKitModule.version());/* */function/* */getPeptideBonds(mol){let/* */peptide_bond="CC(=O)NC";let/* */qmol=window.RDKitModule.get_qmol(peptide_bond);let/* */matches=JSON.parse(mol.get_substruct_matches(qmol));let/* */aggregatedBonds=[];for(let/* */i=0;i<matches.length;i++){match=matches[i];if(Array.isArray(match["bonds"])){aggregatedBonds.push(match["bonds"].slice(-2)[0]);}}return/* */aggregatedBonds;}let/* */smiles="N[C@@H](CC1=CC=C2C(=C1)C(=CN2))(C(=O)N[C@@H](Cc1ccc(O)cc1)(C(=O)N[C@@H](Cc1ccccc1)(C(=O)N[C@@H](CC(=O)O)(C(=O)O))))";let/* */mol=RDKitModule.get_mol(smiles);let/* */mdetails={};mdetails["bonds"]=getPeptideBonds(mol);mdetails["atoms"]=[0];mdetails["highlightColour"]=[0,1,0];mdetails["legend"]="tetrapeptide_4b63";mdetails["explicitMethyl"]=true;canvas=document.getElementById("canvas_b607");mol.draw_to_canvas_with_highlights(canvas,JSON.stringify(mdetails));});/* */</script><p>The tetrapeptide above is shown in its fully neutral (uncharged) drawing form. Using the approximate pKa values below, estimate the <b>net charge</b> of this peptide at pH <b>7.2</b>.</p><p>Sequence (N to C): <span style="font-family: monospace; font-weight: bold;">Trp-Tyr-Phe-Asp</span></p><p>Approximate pKa values for the groups in this peptide:</p><ul><li>alpha-amino group (N-terminus): 9.0</li><li>alpha-carboxyl group (C-terminus): 2.0</li><li>Asp side chain: 3.7</li><li>Tyr side chain: 10.1</li></ul><p>Select the net charge at pH 7.2:</p>	+2	Incorrect	+1	Incorrect	-2	Incorrect	0	Incorrect	-1	Correct