Acyl-CoA: cholesterol acyltransferase(ACAT) is an intracellular enzyme that catalyzes the formation of cholesterol esters from long-chain fatty acyl coenzyme A and cholesterol.

Long-chain acyl-coenzyme A synthetases activate free fatty acid to acyl-CoA thioesters.

A coenzyme present in all living cells that functions as an acyl group carrier and is necessary for fatty acid synthesis and oxidation, pyruvate oxidation, and other acetylation reactions.