If a mutation in the gene that encodes CRP makes it unable to bind to cAMP, which outcome is most likely?

Question

Quizplus · Accepted Answer

CRP (catabolite activator protein) binds to cAMP and then undergoes a change in shape that allows it to bind to the lac operon promoter, leading to increased transcription. If CRP cannot bind to cAMP, it cannot activate the lac operon, leading to lower expression even when glucose is low. The trp operon is not affected by CRP, so its expression is not impacted by this mutation. Option A is incorrect because the presence of lactose is still necessary for induction of the lac operon. Option B is incorrect because high levels of glucose would still inhibit the lac operon regardless of CRP binding. Option D and E are not relevant as they pertain to the trp operon, which is not affected by this mutation.

If a Mutation in the Gene That Encodes CRP Makes