- A membrane-bound organelle occurring in many eukaryotic cells that often has an electron-dense crystalline inclusion containing catalase, urate oxidase, and other oxidative enzymes relating to the formation and degradation of H2O2; thought to be important in detoxifying various molecules and in catalyzing the breakdown of fatty acid s to acetyl-CoA; an absence of peroxisomes is found in individuals with Zellweger syndrome. [peroxide + G. soma, body]
* * *per·ox·i·some pə-'räk-sə-.sōm n a cytoplasmic cell organelle containing enzymes (as catalase) which act esp. in the production and decomposition of hydrogen peroxide called also microbodyper·ox·i·som·al -.räk-sə-'sō-məl adj
* * *n.a small structure within a cell that is similar to a lysosome but contains different enzymes, some of which may take part in reactions involving hydrogen peroxide.
* * *per·ox·i·some (pər-okґsĭ-sōm) a microbody (q.v.), present in all animal cells except erythrocytes and many plant cells, containing over 50 enzymes that participate in a variety of oxidative processes, including reactions involving hydrogen peroxide, purine metabolism, cellular lipid metabolism, and gluconeogenesis. Similar structures (glyoxysomes), containing the enzymes of the glyoxylate cycle, are found in certain plants and microorganisms. Defects in peroxisome biosynthesis cause adrenoleukodystrophy and cerebrohepatorenal (Zellweger) syndrome.
Medical dictionary. 2011.