High level expression of the lac operon requires

Question

Quizplus · Accepted Answer

High level expression of the lac operon requires low glucose and high lactose. This is because when glucose is low, the lac repressor protein is not bound to the operator region and the activator protein CAP is bound to its regulatory region, allowing RNA polymerase to bind to the promoter and transcribe the lac genes. High lactose levels provide the substrate for the production of lactose-metabolizing enzymes, leading to high expression of the lac operon. High glucose levels can actually inhibit the expression of the lac operon by decreasing the levels of cAMP, which is needed for CAP to bind to its regulatory region.

High Level Expression of the Lac Operon Requires