Peroxisome

Peroxisomes are ubiquitous organelles in eukaryotes. They consist of a single membrane that separates them from the cytosol (the internal fluid of the cell). Peroxisomes were discovered by Christian de Duve in 1965. Unlike lysosomes, peroxisomes are not formed in the Golgi apparatus, but self-replicate by dividing Peroxisomes normally enlarge then divide. Peroxisomes are 0.2-1 micrometers and are most abundant in the liver.

Functions

One of the main functions of peroxisomes is to detoxify the cell by splitting hydrogen peroxide. They contain the enzyme catalase. Catalase converts H₂O₂ (hydrogen peroxide, a toxic byproduct of cellular metabolism) to H₂O and O₂, with 4H₂O₂ → 4H₂O + 2O₂.

Peroxisomes also degrade fatty acids and toxic compounds and catalyze the first two steps in the synthesis of ether phospholipids, which are later used to build membranes. Peroxisomes are responsible for oxidation of long-chain fatty acids and thereby generating acetyl groups. Peroxisomes contain other oxidative enzymes such as D-amino acid oxidase and urease oxidase.