Question

Which of the following mutations would make Lac operon regulation unresponsive to glucose levels.

a. A mutation in CRP that makes it unable to bind cAMP
b. A mutation in LacI that makes it unable to bind lactose
c. A mutation in LacI that makes it unable to bind glucose
d. A mutation in CRP that makes it unable to bind glucose

Answer 1

Answer:

A

Explanation:

The lac (lactose) operon is made up of a group of genes that encodes for proteins that are responsible in converting lactose into glucose.The lac operon is found in bacteria such as E.coli , and it is made up of three structural genes:

1. lacZ
2. lacY
3. lacA

Answer 2

Glucose stops activation of the lac operon, thereby preventing the use of lactose. Thus, a mutation in CRP that makes it unable to bind cAMP would make Lac operon regulation unresponsive to glucose levels (Option d).

• The lac operon is a group of genes that are required for the uptake and metabolism of lactose in bacteria.

• This operon (lac operon) is positively regulated by low glucose levels. When the intracellular glucose level is low, then the level of a small molecule called cyclic AMP (cAMP) is high.

• The AMP receptor protein (CRP), also known as catabolite activator protein or CAP, forms a complex with cAMP, which acts as a positive regulator of the lac operon.

• The CRP-cAMP complex then binds to a specific DNA sequence upstream of the lac operon, thereby enhancing RNA polymerase binding and leading to the activation of gene expression from the lac operon.

In conclusion, a mutation in CRP that makes it unable to bind cAMP would make Lac operon regulation unresponsive to glucose levels (Option d).

Learn more in:

https://brainly.com/question/9739412