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PLA2_plant: Plant-specific sub-family of Phospholipase A2, a super-family of secretory and cytosolic enzymes; the latter are either Ca dependent or Ca independent. Enzymatically active PLA2 cleaves the sn-2 position of the glycerol backbone of phospholipids; secreted PLA2s have also been found to specifically bind to a variety of soluble and membrane proteins in mammals, including receptors. As a toxin, PLA2 is a potent presynaptic neurotoxin which blocks nerve terminals by binding to the nerve membrane and hydrolyzing stable membrane lipids. The products of the hydrolysis cannot form bilayers leading to a change in membrane conformation and ultimately to a block in the release of neurotransmitters. PLA2 may form dimers or oligomers. This sub-family does not appear to have a conserved active site and metal-binding loop.