Phospholipase A2, histidine active site QuickView

Description:: Phospholipase A2 (PLA2) is a small lipolytic enzyme that releases fattyacids from the second carbon group of glycerol. It is involved in a numberof physiologically important cellular processes, such as the liberation of arachidonicacid from membrane phospholipids. It plays a pivotal role in the biosynthesis of prostaglandin and othermediators of inflammation. PLA2 has four to seven disulphide bonds and binds a calciumion that is essential for activity. Within the active enzyme, the alpha amino group isinvolved in a conserved hydrogen-bonding network linking the N-terminal region tothe active site. The side chains of two conserved residues, His and Asp, participate inthe catalytic network.Many PLA2's are widely distributed in snakes, lizards, bees and mammals. In mammalsthere are at least four forms: pancreatic, membrane-associated as well as two lesswell characterised forms. The venom of most snakes contains multiple forms of PLA2.Some of them are presynaptic neurotoxins which inhibit neuromuscular transmission byblocking acetylcholine release from the nerve termini. This entry represents the PLA2 active site histidine and contains three cysteines involved in disulfide bonds.

QuickView for Phospholipase A2, histidine active site (biogroup)