MCB 3020L Lecture Notes - Lecture 13: Luciferase, Maltose, Enzyme
Document Summary
Crp: cyclic amp (camp) signal molecule for crp protein. cyclic adenosine monophospahte builds up in the cells when the bacteria runs out of glucose. The effect of glucose repressing genes for other sugars is known as catabolite repression. More than one gene transcribed together to give a single mrna. Activation of the lac operon is dependant on the regulatory proteins laci and crp. Need the presence of allalactose to inactivate laci. Need to absence of glucose for camp to activate crp. We only get expression of the lac operon when lactose is present and glucose is absent. Overview of dual regulation of the lac operon: glucose+ / lactose+ No crp: camp bound/ laci inactivated: glucos+/ lactose - No crp: camp bound/ laci activated: glucose-/ lactose- Crp: camp binds/ laci activated: glucose -/ lactose + Crp + camp activates transcription for the mait.
