Question

Can you explain how I can assess mutant phenotypes to determine whether mutations affect regulatory regions of DNA, regulatory proteins, or structural genes? Mutants may be normally haploid or partially diploid bacteria (containing F' plasmids).

Answer 1

First, to identify on which gene the mutation is present, you need to grow bacteria on various different auxotrophic plates. By replica plating on different auxotrophic plates you could identify the mutant.

Now that you know the mutant gene, you need to know wether Mutation is in its structural gene or regulator region or regulatory proteins. To identify these sites of mutation, you need to perform complementation studies for different regions of that gene to identify on exactly which region the Mutation is present.