English Lectures / lipids 2 ENG

Fatty Acid Biosynthesis

3. The formation of malonyl-SCoA from acetylSCoA.

The carboxylation of acetyl-SCoA is catalyzed by acetyl-SCoA-carboxylase, an enzyme complex of three enzymes.

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Fatty Acid Biosynthesis

4. Synthesis of palmitic acid.

It is carried out by a multi-enzyme complex "synthase of fatty acids" (a synonym for palmitate synthase), which includes 6 enzymes and an acyl-transporting protein (APB).

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Fatty Acid Extension

•Synthesized palmitic acid, if necessary, enters the endoplasmic reticulum. Here, with the participation of malonyl-S-CoA and NADP, the chain is extended to C18 or C20. The addition of carbons proceeds through the carboxyl group (C1).

•Unsaturated fatty acids (oleic, linoleic, linolenic) can also be lengthened with the formation of eicosanoic acid derivatives (C20). But the double bond of animal cells is introduced no further than 9 carbon atoms, therefore, ω3and ω6polyunsaturated fatty acids are synthesized only