Question

Which of the following takes place due to phosphorylation of isocitrate dehydrogenase?

(a) Inhibits the binding of citrate at active site

(b) Degrades the enzyme

(c) Enhances the substrate-binding affinity

(d) No reaction

I got this question during an online interview.

My question is from Regulatory Enzymes in chapter Enzymes, Carbohydrates and Gycobiology of Biochemistry

Answer 1

Right option is (a) Inhibits the binding of citrate at active site

For explanation I would say: The electrostatic repulsion by the phosphoryl group inhibits the binding of citrate at active site.