In fatty acid synthesis CO2 step loss occurs in which?
Ans. C. Condensation reaction(Ref: Harper 31/e page 218)Reactions of Fatty Acid Synthase Complex by three stagesCondensationReductionRelease of fatty acidCondensation Reactions1. Malony/Acetyl transacylase#A priming molecule of acetyl-CoA combines with a cysteine--SH group.#While malonyl-CoA combines with the adjacent-- SH on the 4'-phosphopantetheine of ACP of the other monomer.#These reactions are catalyzed by malonyl acetyl transacylase, to form acetyl (acyl)-malonyl enzyme2. Ketoacyl synthase#The acetyl group attacks the methylene group of the malonyl residue, catalyzed by 3-ketoacyl synthase, and liberates CO2 , forming 3-ketoacyl enzyme (aceto acetyl enzyme) (reaction2), freeing the cysteine--SH group.
Hydration
Dehydration
Condensation reaction
Reduction
Lipids