Fatty acid recycling and degradation
This pathway mainly shows the oxidation of fatty acids. The fatty acid oxidation takes place in mitochondria in animals. This is the reverse of fatty acid biosynthesis and utilises CoA as acyl carrier. The four main enzymes involved in the degradation of fatty acids are acyl-CoA oxidase (acyl-CoA dehydrogenase), Enoyl-CoA hydratase, 3-hydroxyacyl-CoA dehydrogenase and 3-oxoacyl-CoA thiolase. Each cycle of activities of these enzymes removes 2-carbon units in the form of acetyl-CoA. This cycle of activities can continue until the fatty acid chain is degraded to 4-carbon acetoacetyl-CoA. Acetoacetyl-CoA can then be cleaved to 2 acetyl-CoAs by the reverse action of the enzyme acetyl-CoA C-acetyltransferase.
This pathway may provide a carbon source in the form of acetyl-CoA for mitochondrial TCA cycle and other biosynthesis pathways. The enzymes acyl-CoA oxidase and 3-hydroxyacyl-CoA dehydrogenase are absent in Plasmodium falciparum. There is no biochemical evidence of this pathway taking place in P. falciparum and therefore not reconstructed in MPMP.
|Enzyme||EC Number||Gene id|
Sources and fates of metabolites
|Substrate||Source pathways||Product||Fate pathways|
|Fatty acid||Fatty acid biosynthesis in the apicoplast, Fatty acid elongation in the cytosol, Fatty acid elongation in the ER, Host||Acetyl-CoA||Fatty acid elongation in the cytosol, Fatty acid elongation in the ER, Fatty acid biosynthesis in the Apicoplast, Tricarboxylic acid (TCA) cycle|