Identification of a human platelet membrane protein alkylated under conditions inhibitory of phospholipase A2 activity.
Platelet membrane sulfhydryls essential for phospholipase A2 activity were alkylated by [3H]N-ethylmaleimide after the non-essential sulfhydryls were cross-linked by azodicarboxylic acid bis(di-methylamide) (DA) or alkylated by N-ethylmaleimide. A 24.5K da protein labeled under phospholipase inhibitory conditions was not labeled under non-inhibitory conditions. The polypeptide, which had neither endogenous nor DA induced disulfides, may be a platelet membrane phospholipase A2 or a lipase regulatory protein.
D000478:Alkylation; D004228:Dithionitrobenzoic Acid / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005033:Ethylmaleimide / Q000494:pharmacology; D006801:Humans; D008970:Molecular Weight; D010740:Phospholipases / Q000097:blood*; D010741:Phospholipases A / Q000097:blood*; D054467:Phospholipases A2; D010980:Platelet Membrane Glycoproteins / Q000032:analysis*
D010980:Platelet Membrane Glycoproteins; D004228:Dithionitrobenzoic Acid; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2; D005033:Ethylmaleimide