-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 FADH2 are passed directly to oxygen,
forming hydrogen peroxide
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 FADH2 are passed directly to oxygen,
forming hydrogen peroxide
.
No ATPs are generated as a result of this electron
transfer, but heat is generated. Peroxisomal -oxidation
also only proceeds as far as C4 and C6
acyl-CoAs. However, the C4 and C6
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.
Oxidation of Saturated Fatty Acids