10: Historical Experiments
Landmark experiments that established core principles of molecular biology: Griffith's transformation experiment, Avery-MacLeod-McCarty's identification of DNA as the transforming principle, Hershey-Chase's confirmation that DNA carries genetic information, and Beadle-Tatum's one gene-one enzyme hypothesis linking genes to proteins.
Bacterial Nutrient Requirements in Mutant Metabolic Pathways (5 Metabolites)
Click to show Bacterial Nutrient Requirements in Mutant Metabolic Pathways (5 Metabolites) example problem
| enzyme 1 | enzyme 2 | enzyme 3 | enzyme 4 | |||||
| A | ⟶ | D | ⟶ | N | ⟶ | R | ⟶ | X |
Look at the metabolic pathway in the table above.
Metabolite X is needed for the bacteria to grow.
Consider a bacterial strain that is mutant for the gene coding for enzyme 1
Which nutrients, when added to minimal media, will help this bacteria grow?
Multiple answers may be correct.
Metabolic Pathway Precursor Order from Mutant Growth Data (4 Metabolites)
Click to show Metabolic Pathway Precursor Order from Mutant Growth Data (4 Metabolites) example problem
A mutant screen was carried out to produce the diagram below. The diagram shows different classes (1-4) of mutants for metabolic precursors (W-Z) of a metabolic pathway to produce a product were characterized to either grow (+) or not grow (–) in minimal media.
| W | X | Y | Z | |
| Class 1 | – | + | – | – |
| Class 2 | + | + | + | – |
| Class 3 | – | + | + | – |
| Class 4 | + | + | + | + |