Inactivation of various proteinase inhibitors and the complement system in human plasma by the 56-kilodalton proteinase from Serratia marcescens.
The interaction of the 56-kilodalton (kDa) proteinase from Serratia marcescens with human plasma activated C1 (C1) inhibitor, alpha 2-antiplasmin, and antithrombin III was investigated. The 56-kDa proteinase was not affected by these inhibitors; on the contrary, all the inhibitors were inactivated by the 56-kDa proteinase within 2 to 6 h. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that all three inhibitors showed decreases in molecular weight of approximately 8,000 to 10,000 as a result of proteolytic cleavage by the 56-kDa proteinase. The 56-kDa proteinase also inactivated serum complement within 2 to 6 h. The loss of inhibitory activity caused by the 56-kDa proteinase, together with the effects of endogenous serine proteinases, may facilitate tissue destruction and inflammation.
Molla
A
A
Department of Microbiology, Kumamoto University School of Medicine, Japan.
Akaike
T
T
Maeda
H
H
D003174:Complement C1 Inactivator Proteins / Q000378:metabolism; D003169:Complement Inactivator Proteins / Q000494:pharmacology*; D006461:Hemolysis; D006801:Humans; D006868:Hydrolysis; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000502:physiology*; D008970:Molecular Weight; D011480:Protease Inhibitors / Q000097:blood*; D012706:Serratia marcescens / Q000201:enzymology* / Q000502:physiology; D000979:alpha-2-Antiplasmin / Q000494:pharmacology
D003174:Complement C1 Inactivator Proteins; D003169:Complement Inactivator Proteins; D011480:Protease Inhibitors; D000979:alpha-2-Antiplasmin; D008666:Metalloendopeptidases; C044194:microbial metalloproteinases