Which of the following exerts a positive allosteric effect on de novo fatty acid synthesis at the level of acetyl-CoA carboxylase?
A) acetyl-CoA
B) AMPK
C) ATP
D) biotin
E) citrate

Question

Quizplus · Accepted Answer

Citrate acts as a positive allosteric effector of acetyl-CoA carboxylase, the enzyme that catalyzes the rate-limiting step in fatty acid synthesis. It facilitates the polymerization of the enzyme, enhancing its activity.  Both isoforms of ACC are allosterically activated by citrate and inhibited by palmitoylCoA and other short- and long-chain fatty acyl-CoAs. Citrate triggers the polymerization of ACC1 which leads to significant increases in its activity. Although ACC2 does not undergo significant polymerization (presumably due to its mitochondrial association), it is allosterically activated by citrate. Glutamate and other dicarboxylic acids can also allosterically activate both ACC isoforms.

Which of the Following Exerts a Positive Allosteric Effect on De