Which one of the following cofactors must be utilized during the conversion of acetyl CoA to malonyl CoA?
Correct Answer: Biotin
Description: The key enzymatic step of fatty acid synthesis is the carboxylation of acetyl CoA to form malonyl CoA. The carboxyl of biotin is covalently attached to an e-amino acid group of a lysine residue of acetyl CoA carboxylase. The reaction occurs in two stages. In the first step, a carboxybiotin is formed: HCO3- + biotin-enzyme + ATP - CO2-biotin-enzyme + ADP + Pi In the second step, the CO2 is transferred to acetyl CoA to produce malonyl CoA: CO2-biotin-enzyme + acetyl CoA -- malonyl CoA + biotin-enzyme None of the other cofactors listed are involved in this reaction. Ref:Bender D.A. (2011). Chapter 44. Micronutrients: Vitamins & Minerals. In D.A. Bender, K.M. Botham, P.A. Weil, P.J. Kennelly, R.K. Murray, V.W. Rodwell (Eds),Harper's Illustrated Biochemistry, 29e.
Category:
Biochemistry
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now