Active Site

Phospholipase A2, histidine active site (IPR033113)

Short name: PLipase_A2_His_AS

Description

Phospholipase A2 (EC:3.1.1.4) (PLA2) is a small lipolytic enzyme that releases fatty acids from the second carbon group of glycerol. It is involved in a number of physiologically important cellular processes, such as the liberation of arachidonic acid from membrane phospholipids [PMID: 7664098]. It plays a pivotal role in the biosynthesis of prostaglandin and other mediators of inflammation. PLA2 has four to seven disulphide bonds and binds a calcium ion that is essential for activity. Within the active enzyme, the alpha amino group is involved in a conserved hydrogen-bonding network linking the N-terminal region to the active site. The side chains of two conserved residues, His and Asp, participate in the catalytic network [PMID: 2480893].

Many PLA2's are widely distributed in snakes, lizards, bees and mammals. In mammals there are at least four forms: pancreatic, membrane-associated as well as two less well characterised forms. The venom of most snakes contains multiple forms of PLA2. Some of them are presynaptic neurotoxins which inhibit neuromuscular transmission by blocking acetylcholine release from the nerve termini.

This entry represents the PLA2 active site histidine and contains three cysteines involved in disulfide bonds.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns