Which of the following enzymes, requires Biotin as the coenzyme: (A) Pyruvate Dehydrogenase, (B) Pyruvate Kinase, (C) Pyruvate Carboxylase, (D) PEP Carboxy Kinase
Answer is C. Pyruvate enters the mitochondrion and is carboxylated to oxaloacetate by pyruvate carboxylase, an ATP-dependent reaction in which the coenzyme is the Vitamin biotin.Ref: Harper&;s Biochemistry; 30th edition; Chapter 16; The Citric Acid Cycle: The Central Pathway of Carbohydrate, Lipid & Amino Acid Metabolism