PURIFICATION AND SOME PROPERTIES OF A PHOSPHOLIPASE-A2 FROM BOVINE PLATELETS

An intracellular form of phospholipase A2 was purified about 47,500-fold to near homogeneity from bovine platelets 100,000 × g supernatant by sequential use of column chromatographies on Heparin-Sepharose, DEAE-Sephacel, Butyl-Toyopearl, Sephacryl S-300, DEAE-5PW HPLC, TSK G 3000 SW HPLC and Mono Q FPLC. The final preparation showed a single band on SDS-polyacrylamide gel, and its molecular mass was estimated to be approximately 100,000 daltons. The purified PLA2 showed maximal activity at alkaline pH(pH 9.0-10.0) and considerable activity at 0.3-1.0μM calcium concentration. It hydrolyzed phosphatidylcholine containing arachidonate at sn-2 position with high selectivity in comparison to linoleate. © 1991.