Acetoacetyl-CoA

Acetoacetyl-CoA is an intermediate in fatty acid oxidation, cholesterol biosynthesis and ketone body metabolism (ketogenesis) participating in the following reactions:

1. 2 Acetyl-CoA <=> Acetoacetyl-CoA + CoASH (Catalyzed by Thiolase).

2. Acetoacetyl-CoA + Acetyl-CoA <=> HMG-CoA + CoASH (Catalyzed by HMG-CoA Synthase)

3. Acetoacetate + Succinyl-CoA <=> Acetoacetyl-CoA + Succinate (Catalyzed by 3-Ketoacyl-CoA Transferase).

Reaction #1 is a reversal of the last step of fatty acid oxidation.