Fatty-acyl-CoA synthase
Fatty acids are key components of a cell, therefore, the regulation or inhibition of fatty acid synthesis hold severe consequences for cellular function. The malfunction of the fatty acid synthesis pathway can result in cancer and obesity. However, the significance of fatty acid synthesis also make the fatty acid synthesis pathway a potential target for the search and study of anticancer and antibiotic drugs. It has been found that in humans, fatty acid synthase, is overly expressed in cancer cells. Therefore, FAS, which has been associated only with energy production prior, is now associated with aggressive tumor growth and survival. Studies have also found that human fatty acid synthase is overly expressed in prostate cancer cells.
Fatty acid synthesis
In mammals the aerobic desaturation is catalyzed by a complex of three membrane-bound enzymes ("NADH-cytochrome b reductase, cytochrome b", and a "desaturase"). These enzymes allow molecular oxygen, O, to interact with the saturated fatty acyl-CoA chain, forming a double bond and two molecules of water, HO. Two electrons come from NADH + H and two from the single bond in the fatty acid chain. These mammalian enzymes are, however, incapable of introducing double bonds at carbon atoms beyond C-9 in the fatty acid chain..) Hence mammals cannot synthesize linoleate or linolenate (which have double bonds at the C-12 (= Δ), or the C-12 and C-15 (= Δ and Δ) positions, respectively, as well as at the Δ position), nor the polyunsaturated, 20-carbon arachidonic acid that is derived from linoleate. These are all termed essential fatty acids, meaning that they are required by the organism, but can only be supplied via the diet. (Arachidonic acid is the precursor the prostaglandins which fulfill a wide variety of functions as local hormones.)