title: Purification and characterization of phospholipase A2 released from rat platelets.
abstract: It was found that phospholipase A2 and lysophospholipase, both of which were released from thrombin-stimulated rat platelets, had high affinity to insolubilized heparin. Phospholipase A2 released from rat platelets was purified by the sequential use of column chromatography on heparin-Sepharose and TSK gel G2000SW (high-performance liquid chromatography, HPLC). The enzyme was near homogeneous on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and HPLC, and its Mr was estimated to be 13,500. The purified enzyme was labile and lost its activity within 1 h when incubated at 37 degrees C. Phospholipids or detergent in the solution protected the enzyme against inactivation. Phospholipase activity was inhibited by p-bromophenacylbromide, but not by diisopropylfluorophosphate or iodoacetamide. Lysophospholipase, which was also released from rat platelets, was separated from phospholipase A2 by chromatography on heparin-Sepharose.
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000201:enzymology*; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D007700:Kinetics; D017830:Octoxynol; D010740:Phospholipases / Q000302:isolation & purification*; D010741:Phospholipases A / Q000302:isolation & purification*; D054467:Phospholipases A2; D011092:Polyethylene Glycols / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D011092:Polyethylene Glycols; D017830:Octoxynol; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2