Question 24.5: Malonyl ACP is required for the elongation of fatty acid cha...

a.  Acetyl CoA combines with bicarbonate to fonn malonyl CoA, which reacts with ACP to form malonyl ACP.
     Acetyl  CoA + HCO_{3}^{-} + ATP → malonyl  CoA + ADP + P_{i} + H^{+}
     Malonyl  CoA + HS — ACP → malonyl  ACP + HS — CoA
b.  The enzyme for the first reaction is acetyl CoA carboxylase. The enzyme for the second reaction is malonyl CoA transacylase.