Hydroxy-Methyl-Glutaryl-CoA Synthase (HMG-CoA Synthase)

HMG-CoA Synthase catalyzes the reaction below:

Acetoacetyl-CoA + Acetyl-CoA <=> HMG-CoA + CoASH

This reaction is important in ketogenesis and in cholesterol metabolism, because HMG-CoA is a branch point between the two pathways.