Propionyl-CoA is obtained as an end product of isoleucine valine and methionine catabolism. It is an essential component for the methylaspartate cycle. Branched-chain amino acids and cholesterol also give rise to propionyl-CoA. Propionyl coenzyme A (CoA) is the coenzyme A derivative of propionic acid. Propionyl CoA is formed during the -oxidation of odd-chain fatty acids.