Fatty Acid Synthetases of Eukaryotic Cells

The synthesis of long-chain fatty acids, such as palmitic, occurs in the living cell by head-to-tail condensation of C2 units as acetyl-CoA. The condensation occurs in two steps. First, acetyl-CoA is converted to malonyl-CoA by acetyl-CoA carboxylase, a multienzyme system containing biotin [Eq. (1); for a recent review see Wakil et al., 1983]. The second step (Eq. 2) is the conversion of acetyl-CoA and malonyl-CoA to palmitate, catalyzed by fatty acid synthetases (FAS) in the presence of NADPH.