Malonyl-CoA is an intermediate in fatty acid synthesis. It also regulates fatty acid metabolism. Which of the molecules regulate the enzyme that catalyzes malonyl‑CoA synthesis? carnitine acetyl-CoA oxaloacetate fatty acids or fatty acyl-CoA citrate Which of the enzymes does malonyl‑CoA regulate? carnitine acyltransferase acyl-CoA dehydrogenase fatty acid synthase ATP-citrate lyase acetyl-CoA carboxylase Determine how each of the choices affects fatty acid synthesis and β‑oxidation. inhibits fatty acid synthesis inhibits β‑oxidation Answer Bank

Fatty acid is the the molecule that regulates the enzymes that catalyzes malonyl - CoA synthesis. This enzyme is Acetyl - Co-A carboxylase. It catalytic activity is regulated fatty acid by covalent modification and allosteric control.

Carnitine acytransferase is the enzyme that malonyl-CoA regulates. The latter prevents fatty acids from combining with carnitine, therefore blocking their entry into the mitochondria, inhibiting fatty acid oxidation and degradation

If the concentration of fatty acid in the cytosol is increased, the production of fatty acid in the cell is inhibited. Likewise beta - oxidation synthesis is inhibited with high concentration of Melonyl-CoA.