Question

Pyruvate (pyruvic acid) dehydrogenase is used in converting

• A. Pyruvate to glucose
• B. Glucose to pyruvate
• C. Pyruvic acid to lactic acid
• D. Pyruvate to acetyl CoA

Answer 1

Answer: (D)

Pyruvate to acetyl CoA

The pyruvic acid generated in the glycolysis enters into the mitochondrial matrix, undergoes oxidative decarboxylation and forms active acetate in a coordinated series of reactions catalysed by the multienzyme complex. The reaction takes place in the presence of enzyme pyruvate dehydrogenase and several coenzymes including $NA{D}^{+}$, coenzyme A, thiamine pyrophosphate and lipoic acid. The reaction occurs in 4 steps involving the conversion of pyruvic acid to acetyl coenzyme A. One molecule of carbon dioxide is released. The coenzyme $NA{D}^{+}$ is reduced to $NADH+H^{+}$ in the reaction.

Thus, the correct answer is option D.