Pyruvic acid is oxidized to acetyl Co, producing NADPH+H+ and CO2. It is an oxidative decarboxylation process. Pyruvic acid produces acetyl Co-A stepwise in oxidative decarboxylation process. The enzyme pyruvic dehydrogenase plays a role in this reaction. The process is –
1. In the presence of decarboxylase enzyme, pyruvic acid and thiamine pyrophosphate (TPP) react to form thiamine pyrophosphate compound (TPP).
2. In the presence of trans acetylase enzyme, TPP compounds and lipoic acid react to produce acetyl lipoic acid. At this time TPP was released.
3. Acetyl lipoic acid reacts with Co-A to form Acetyl Co-A. At this time lipoic acid is oxidized.