Overview Structure membrane-bound vesicle contain several important enzymes catalase hydrogen-transferring enzymes lipid oxidizing enzymes Refsum disease autosomal recessive due to mutations in PHYH or PEX7 gene resulting in defects in alpha-oxidation leading to a build up of phytanic acid presentation vision loss anosmia Function degradation of very long chain fatty acids (VLCFAs) > 24 carbons via β-oxidation reduces by 14 carbons and then sends to mitochondria deficient in Zellweger syndrome build-up of VLCFAs in peroxisomes impaired myelin synthesis severe neurological symptoms hepatomegaly death < 1 year can increase lifespan with diet low in VLCFAs AR other examples of peroxisomal disorders neonatal adrenoleukodystrophy (NALD) bile acid synthesis derived from cholesterol phospholipid modification alter phosphatidylserine and phosphatidylethanolamine degradation of hydrogen peroxide via catalase degrades hydrogen peroxide produced in β-oxidation of fatty acids