Gene regulation governing lactose operon of E. coli that involves the lac I gene product is:

Question

Gene regulation governing lactose operon of E. coli that involves the lac I gene product is: (A) Positive and inducible because it can be induced by lactose (B) Negative and inducible because repressor protein prevents transcription (C) Negative and repressible because repressor protein prevents transcription (D) Feedback inhibition because excess of β - galactosidase can switch off transcription

Tardigrade Admin · Accepted Answer

In negative regulation, a repressor molecule binds to the operator of an operon and terminates transcription. The lac operon is a negatively controlled inducible operon, where the inducer molecule is allolactose.

Q. Gene regulation governing lactose operon of E. coli that involves the lac I gene product is:

Positive and inducible because it can be induced by lactose

Negative and inducible because repressor protein prevents transcription

Negative and repressible because repressor protein prevents transcription

Feedback inhibition because excess of $β$ - galactosidase can switch off transcription

In negative regulation, a repressor molecule binds to the operator of an operon and terminates transcription. The lac operon is a negatively controlled inducible operon, where the inducer molecule is allolactose.