Coenzyme A (CoA, CoASH, or HSCoA) is adapted from pantothenic
acid and adenosine triphosphate and used in metabolism in areas
such as fatty acid oxidization and the citric acid cycle. Its
main function is to carry acyl groups such as acetyl as
thioesters. A molecule of coenzyme A carrying an acetyl group is
also referred to as acetyl-CoA. Acetyl-CoA is an important
molecule itself. It is the precursor to HMG CoA, which is a
vital component in cholesterol and ketone synthesis.
Furthermore, it contributes the acetyl group to acetylcholine;
the addition of the acetyl group to choline a reaction that is
catalysed by choline acetyltransferase. Its main task is
conveying the carbon atoms within the acetyl group to the citric
acid cycle to be oxidized for energy production. The conversion
of pyruvate into Acetyl-CoA is referred to as the Pyruvate
Dehydrogenase Reaction. It is catalyzed by an enzyme-complex
called pyruvate dehydrogenase. The enzyme consists of 60
subunits: 24 pyruvate dehydrogenase, 24 dihydrolipoyl