Heterotrimer: Snake venom phospholipase A2 (PLA2) heterotrimer that acts as a potent presynaptic neurotoxin by blocking synaptic transmission and synaptic vesicle recycling (PubMed:17313963). May act by binding in a calcium-dependent fashion to neurotonal pentraxin-1 (NPTX1) and neurotonal pentraxin-2 (NPTX2), but not to neuronal pentraxin receptor (NPTXR). Also binds to taipoxin-associated calcium binding protein 49 (RCN2), a protein localized in the lumen of endoplasmic reticulum (By similarity). Monomer (alpha chain): Snake venom phospholipase A2 (PLA2) alpha chain that possesses the same high enzymatic activity than the heterotrimer. PLA2 catalyzes the calcium-dependent hydrolysis of the 2-acyl groups in 3-sn-phosphoglycerides (By similarity). 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. Heterotrimer of alpha, beta, and gamma chains; non-covalently linked. Expressed by the venom gland. Belongs to the phospholipase A2 family. Group I subfamily. D49 sub-subfamily. The assignment of paradoxin function to this sequence has been made based on sequence similarity to taipoxin and cannitoxin. The gamma chain has not yet been sequenced.