Molecular cloning of phospholipase A2 from a Thai Russell's viper venom gland cDNA library.

Snake venom contains several toxins. Russell's viper (D. russellii, RV) is a venomous snake prevalent in northern and central Thailand. RV bites can cause disseminated coagulation, hemolysis, and edema of the bitten limbs. To identify protein components of RV venom, we made a cDNA library from RV venom glands, and randomly sequenced cloned cDNA. We were able to clone a cDNA encoding RV phospholipase A2 (PLA2). PLA2 is an active enzyme found in several species of snake venom worldwide. PLA2 is thought to be toxic to cell membrane, thereby, can cause local cell and tissue damage, as well as systemic effects in snake bite victims. This PLA2 cDNA clone would facilitate in vivo studies of the pathophysiology of RV bite.