Phospholipase A2
Phospholipases A2 (PLA2s) EC 3.1.1.4 are enzymes that release fatty acids from the second carbon group of glycerol. This particular phospholipase specifically recognizes the sn-2 acyl bond of phospholipids and catalytically hydrolyzes the bond releasing arachidonic acid and lysophospholipids. Upon downstream modification by cyclooxygenases, arachidonic acid is modified into active compounds called eicosanoids. Eicosanoids include prostaglandins and leukotrienes, which are categorized as inflammatory mediators.
PLA2 are commonly found in mammalian tissues as well as insect and snake venom. Venom from both snakes and insects is largely composed of melittin, which is a stimulant of PLA2. Due to the increased presence and activity of PLA2 resulting from a snake or insect bite, arachidonic acid is released from the phospholipid membrane disproportionately. As a result, inflammation and pain occur at the site. There are also prokaryotic A2 phospholipases.
Additional types of phospholipases include phospholipase A1, phospholipase B, phospholipase C, and phospholipase D.
Read more about Phospholipase A2: Families, Mechanism, Regulation, Relevance in Neurological Disorders, Isozymes