Inactivation of Single - Chain Urokinase ( Pro - urokinase ) by Throm bin and Thrombin - like Enzymes :
نویسنده
چکیده
Whereas crude bovine thrombin activated single-chain urokinase-type plasminogen activator (scu-PA), otherwise called pro-urokinase (pro-UK). purified human thrombin converted pro-UK (scu-PA) to a two-chain form that had no amidolytic activity. The two chains (M 33.000 and 22.000) were disulfide linked and resistant to subsequent activation by plasmin. By contrast. thrombin did not mactivate tissue plasminogen activator or two-chain urokinase. The enzyme from snake venom Agkistrodon contortrix, relatively specific for fibrinopeptide B. had an effect similar to thrombin, whereas the enzyme from Agkistrodon rhodostoma (ancrod). specific for fibrinopeptide A. did not. When pro-UK (scu-PA) was present during thrombin clotting of fibrinogen. degradation of 125l-pro-UK (scu-PA) in the clot supernatant was seen. whereas virtually full recovery (95%) of radioactivity was found. A loss of latent
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Inactivation of Single - Chain Urokinase ( Pro - urokinase ) by Throm bin and Thrombin - like Enzymes : Relevance of the
Whereas crude bovine thrombin activated single-chain urokinase-type plasminogen activator (scu-PA), otherwise called pro-urokinase (pro-UK). purified human thrombin converted pro-UK (scu-PA) to a two-chain form that had no amidolytic activity. The two chains (M 33.000 and 22.000) were disulfide linked and resistant to subsequent activation by plasmin. By contrast. thrombin did not mactivate tis...
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Whereas crude bovine thrombin activated single-chain urokinase-type plasminogen activator (scu-PA), otherwise called pro-urokinase (pro-UK), purified human thrombin converted pro-UK (scu-PA) to a two-chain form that had no amidolytic activity. The two chains (Mr approximately 33,000 and 22,000) were disulfide linked and resistant to subsequent activation by plasmin. By contrast, thrombin did no...
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The in vitro effects of thrombomodulin on the inactivation of single chain urokinase-type plasminogen activator (scu-PA) by thrombin were investigated by incubating scu-PA with varying concentrations of human thrombin, in both the absence and presence of soluble rabbit thrombomodulin. 50% inactivation of scu-PA occurred in 45 min at 160 ng/ml thrombin in the absence of thrombomodulin and at 4.6...
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BACKGROUND Excessive fibrin deposition within the inflamed joints of rheumatoid arthritis (RA) patients suggests that local fibrinolysis is inefficient, which seems to be in contrast with the observed increased levels of urokinase type plasminogen activator (u-PA). Thrombin-mediated inactivation of single chain u-PA (scu-PA) into an inactive form called thrombin-cleaved two chain u-PA (tcu-PA/T...
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