The major function of peroxisomes is:
Peroxisomes are single membrane oxidative organelles discovered by Rhodin and De Duve, numbering hundreds per cell, containing more than fifty enzymes producing and degrading hydrogen peroxide. Beta-oxidation of very long chain fatty acids greater than twenty two carbons, branched phytanic acid alpha-oxidation, bile acid intermediate shortening and ether lipid synthesis of plasmalogens providing antioxidant membranes and myelin components occur via enzymes acyl-CoA oxidase generating H2O2, bifunctional enzyme and thiolase. Catalase converts two H2O2 to water and oxygen detoxifying, also urate oxidase and D-amino acid oxidase produce peroxide. Import depends on peroxisomal targeting signals PTS1 tripeptide SKL at C terminus recognized by Pex5 receptor and PTS2 nonapeptide recognized by Pex7. Protein degradation via lysosomal hydrolases acidic, ATP synthesis mitochondrial inner membrane, nucleic acid processing nuclear. Defects in Pex genes cause Zellweger spectrum with accumulation of very long chain fatty acids, hypotonia and neuronal migration failure illustrating essential lipid metabolic and detoxification function distinct from energy metabolism.
Ref: Wanders Annu Rev Biochem; peroxisome beta-oxidation VLCFA catalase PTS1 PTS2 Pex import.