How do bacteria avoid wasteful production of unnecessary proteins when their genes are always on? The answer lies in regulating the operon. As trp levels increase, trp binds to trpR, causing a ...

The gene lacI, which encodes the lac repressor, LacI, sits outside the operon and is constitutively expressed. A cyclic adenosine monophosphate (cAMP) receptor protein (CRP) binding site (C) sits in ...

Last week I finally addressed promoters and gave a bit of background on the lac operon. Looking back, I feel that I didn't give the topic of operons adequate treatment. They are a very crucial aspect ...