Characterization of the interaction of bovine plasmin with Streptococcus uberis.
The binding of plasmin to Streptococcus uberis strain 0140 J was optimal in the pH range 5.0-5.5. Plasmin binding decreased exponentially with increasing NaCl concentration (0-0.8 mol l-1), reaching a minimum at NaCl concentrations exceeding 0.55 mol l-1. Neither K+, Mg2+ nor the metal chelator EDTA had any effect on the interaction. Plasmin binding was prevented, in a concentration-dependent manner, by the amino acids lysine, arginine and epsilon-aminocaproic acid. Bound plasmin was also eluted from the bacterial cell using the same amino acids. Bound plasmin was lost from the bacterium in a time- and temperature-dependent fashion, the rate of plasmin loss increased with increasing temperature over the range 4-55 degrees C, and the elution of plasmin from live and heat-killed bacteria was similar. Cell-bound plasmin was only partially inhibited by the physiological inhibitor alpha 2-antiplasmin whereas the serine protease inhibitor aprotinin, and the active site titrant p-nitrophenyl-p-guanidiniobenzoate, inhibited the activity of the cell-bound plasmin by more than 95%.
Institute for Animal Health, Compton Laboratory, Newbury, UK.
R A
RA
Lincoln
J A
JA
Leigh
D000614:Aminocaproates / Q000494:pharmacology; D000818:Animals; D001120:Arginine / Q000494:pharmacology; D002417:Cattle; D004305:Dose-Response Relationship, Drug; D004492:Edetic Acid / Q000494:pharmacology; D005341:Fibrinolysin / Q000032:analysis / Q000378:metabolism*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008239:Lysine / Q000494:pharmacology; D008274:Magnesium / Q000494:pharmacology; D009994:Osmolar Concentration; D011188:Potassium / Q000494:pharmacology; D011480:Protease Inhibitors / Q000494:pharmacology; D013291:Streptococcus / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors
D000614:Aminocaproates; D011480:Protease Inhibitors; D001120:Arginine; D004492:Edetic Acid; D005341:Fibrinolysin; D008274:Magnesium; D008239:Lysine; D011188:Potassium