Peroxisomal Oxidation of Fatty Acids

A modified form of -oxidation of fatty acids occurs in peroxisomes, organelles that are present in most eukaryotic cells. Here electrons are passed to an enzyme-bound form of FAD, but electrons from FADH 2 are passed directly to oxygen, forming hydrogen peroxide

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No ATPs are generated as a result of this electron transfer, but heat is generated. Peroxisomal -oxidation also only proceeds as far as C 4 and C 6 acyl-CoAs. However, the C 4 and C 6 acyl groups can be transferred to carnitine for transport into mitochondria (Figure 18.15), where oxidation can be completed. The function of the peroxisomal pathway is not yet clear, but it probably involves the initial stages in oxidizing very long-chain fatty acids and other lipids.

See also: Oxidation of Saturated Fatty Acids