Question

Given below are two statements, one is labelled as Assertion (A) and other one labelled as Reason (R).

Assertion (A) : Iodoacetate selectively inhibits the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase.
Reason (R) : Iodoacetate is a chelating agent that chelates the magnesium ion and makes it unavailable for the catalytic action of glyceraldehyde-3-phosphate dehydrogenase.

In light of the above statements, choose the correct answer from the options given below.

• A. Both (A) and (R) are true and (R) is the correct explanation of (A).
• B. Both (A) and (R) are true but (R) is NOT the correct explanation of (A).
• C. (A) is true but (R) is false.
• D. (A) is false but (R) is true.

Hint:

Always remember: Iodoacetate inhibits GAPDH by alkylating active-site Cysteine thiol (\(\text{-SH}\)) groups, not by chelating metal ions.

Answer 1

The Correct Option is C