Studies on stereospecific reduction of acetoacetyl CoA and crotonyl CoA in lactating rabbit mammary glands.

Stereospecificity as well as the dependency on reduced pyridine nucleotides of the enzymatic reduction of acetoacetyl CoA and crotonyl CoA in lactating rabbit mammary glands are reported. In the reduction of both acetoacetyl CoA and crotonyl CoA as substrates the tritium from NADP3H was stereospecifically incorporated into the beta-position of n-butyric acid. The reaction of acetoacetyl CoA reduction was much more dependent on NADH while the reduction of crotonyl CoA was rather more dependent on NADPH. There was no difference between the dependencies on NADH and NADPH in the reduction of 2-hexenyl CoA.