An enzyme undergoes a mutation that causes it to lose the ability to be regulated via phosphorylation. Which of the following mutations may lead to this loss of regulation? Assume that the overall structure is not altered by the mutation.
A) Ser $\rightarrow$Thr
B) Thr $\rightarrow$ Ser
C) Tyr $\rightarrow$ Phe
D) Ser $\rightarrow$ Tyr

Question

Quizplus · Accepted Answer

The mutation from Tyrosine (Tyr) to Phenylalanine (Phe) removes a hydroxyl group, which is necessary for phosphorylation. Tyrosine can be phosphorylated, but Phenylalanine cannot, leading to the loss of regulation via phosphorylation.

An Enzyme Undergoes a Mutation That Causes It to Lose →\rightarrow→

An Enzyme Undergoes a Mutation That Causes It to Lose $\rightarrow$