title: Activation of purified human plasma prekallikrein triggered by cell wall fractions of Escherichia coli and Staphylococcus aureus.
abstract: Whether Escherichia coli and Staphylococcus aureus cell wall fractions can trigger the activation of prekallikrein was investigated in a mixture of purified human factor XII, prekallikrein, and high-relative-molecular-weight (Mr) kininogen. After exposure for 30 min to bacterial preparations (0.02-5 mg/ml) at 0 C, lallikrein amidolytic activity was expressed as a percentage of the optimal activation of prekallikrein induced by dextran sulfate. Lipopolysaccharide (LPS) fractions of five E coli strains and lipid A of E coli O111B4 induced 50%-90% optimal activity. However, the polysaccharide fraction induced less than 5% activity. Peptidoglycan and teichoic acid of S aureus induced 70%-100% optimal activity at 5 mg/ml, but protein A did not generate activity. No activation of prekallikrein occurred in the absence of factor XII. Thus, LPS and lipid A of E coli and peptidoglycan and teichoic acid of S aureus can generate kallikrein amidolytic activity in a mixture of purified factor XII, prekallikrein, and high-Mr kininogen.
mesh_terms: D002473:Cell Wall / Q000276:immunology; D004926:Escherichia coli / Q000276:immunology*; D005174:Factor XII / Q000276:immunology; D006801:Humans; D007610:Kallikreins / Q000276:immunology*; D007700:Kinetics; D007704:Kininogens / Q000276:immunology; D008050:Lipid A / Q000276:immunology; D008070:Lipopolysaccharides / Q000276:immunology; D008970:Molecular Weight; D010457:Peptidoglycan / Q000276:immunology; D011288:Prekallikrein / Q000276:immunology* / Q000302:isolation & purification; D013211:Staphylococcus aureus / Q000276:immunology*; D013682:Teichoic Acids / Q000276:immunology; D013997:Time Factors
chemical_list: D007704:Kininogens; D008050:Lipid A; D008070:Lipopolysaccharides; D010457:Peptidoglycan; D013682:Teichoic Acids; D005174:Factor XII; D011288:Prekallikrein; D007610:Kallikreins