Synthesis of acetoacetate by liver enzymes.

Two mechanisms have been proposed for the formation of acetoacetate from acetyl-CoA by liver preparations. With the use of a partially purified system prepared from acetone powders of beef liver, Lynen et al. (1) obtained evidence that acetoacetate formation proceeded via P-hydroxy-fi-methylglutaryl coensyme A as intermediate and involved the HlMG-COAT condensing and HMG-Coh cleavage enzymes as shown in Reactions 1 and 2.