Monomer: snake venom phospholipase A2 (PLA2) that affects neuromuscular transmission presynaptically. It has catalytic activity, anticoagulant activity and weakly inhibits ADP-induced platelet aggregation. PLA2 catalyzes the calcium-dependent hydrolysis of the 2-acyl groups in 3-sn-phosphoglycerides. Heterodimer: shows the same activities as the monomer, but with a lower potency. a 1,2-diacyl-sn-glycero-3-phosphocholine + H2O = a 1-acyl-sn-glycero-3-phosphocholine + a fatty acid + H(+) Binds 1 Ca(2+) ion. Enzymatic activity and neurotoxicity are inhibited by Triton X-100 (By similarity). Triton X-100 has been determined to be located in the center of the hydrophobic channel of the enzyme (PubMed:19500614). Heterodimer of an acidic and a basic chain; non-covalently linked. The toxic basic protein has phospholipase A2 activity (chain HDP-2P) and the non-toxic acidic protein functions as its inhibitor (chain HPD-1I (AC A4VBF0)). Expressed by the venom gland. Belongs to the phospholipase A2 family. Group II subfamily. D49 sub-subfamily.