The role of citrate in fatty acid synthesis makes it an important regulator of the process. Which of the following enzymes would be allosterically activated by citrate?

Question

Quizplus · Accepted Answer

Citrate activates the first committed step of fatty acid biosynthesis, which is the conversion of acetyl-CoA into malonyl-CoA by acetyl-CoA carboxylase. Citrate stimulates acetyl-CoA carboxylase by increasing the enzyme's affinity for its activator, which is bicarbonate, and decreasing its sensitivity to inhibition by long-chain fatty acyl-CoA. Therefore, choice C, acetyl-CoA carboxylase, would be allosterically activated by citrate. Citrate lyase catalyzes the opposite reaction to citrate, and malic enzyme is involved in the malate-aspartate shuttle for NADH transfer. β-ketoacyl-ACP synthase is involved in the elongation step of fatty acid biosynthesis and is not regulated by citrate.

The Role of Citrate in Fatty Acid Synthesis Makes It