Acetyl CoA is necessary for

Transpo of Acetyl CoA to Cytoplasm The staing material for de novo synthesis is acetyl CoA. It is formed inside the mitochondria from pyruvate. The inner membrane is not freely permeable to acetyl CoA. Hence the acetyl CoA units are delivered to the cytoplasm as citrate (Fig. 11.13). Citrate is transpoed from mitochondria by a tricarboxylic acid transpoer. In the cytoplasm, citrate is cleaved to oxaloacetate and acetyl CoA. The enzyme is ATP citrate lyase. The oxaloacetate can return to the mitochondria as malate or pyruvate The first step in the fatty acid synthesis is the carboxylation of acetyl CoA to form malonyl CoA. The acetyl CoA carboxylase is not a pa of the multienzyme complex. But it is the rate-limiting enzyme. Biotin, a member of B complex vitamins, is necessary for this reactionRef: MN Chatterjea Textbook of Medical Biochemistry, 8th Edition, Page no: 136