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Thromb Haemost 1982; 48(01): 024-026
DOI: 10.1055/s-0038-1657208
Original Article
Schattauer GmbH Stuttgart

Kinetics of the Reaction Between Urokinase and an Inhibitor of Fibrinolysis from Placental Tissue

Ulla Christensen
The Chemical Laboratory IV, University of Copenhagen, Copenhagen, Denmark, Department of Pediatrics, Allmänna Sjukhuset, Malmö, Sweden
The Department of Gynecology and Obstetrics, University of Lund, Lund, Sweden
,
L Holmberg
The Chemical Laboratory IV, University of Copenhagen, Copenhagen, Denmark, Department of Pediatrics, Allmänna Sjukhuset, Malmö, Sweden
The Department of Gynecology and Obstetrics, University of Lund, Lund, Sweden
,
B Bladh
The Chemical Laboratory IV, University of Copenhagen, Copenhagen, Denmark, Department of Pediatrics, Allmänna Sjukhuset, Malmö, Sweden
The Department of Gynecology and Obstetrics, University of Lund, Lund, Sweden
,
B Åstedt
The Chemical Laboratory IV, University of Copenhagen, Copenhagen, Denmark, Department of Pediatrics, Allmänna Sjukhuset, Malmö, Sweden
The Department of Gynecology and Obstetrics, University of Lund, Lund, Sweden
› Author Affiliations
Further Information

Publication History

Received 21 September 1981

Accepted 07 May 1982

Publication Date:
13 July 2018 (online)

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Summary

The interaction of urokinase (EC 3.4.21.31) and a protein proteinase inhibitor of fibrinolysis partially purified from placental tissue, which inhibits urokinase but not plasmin, was investigated. The preparations of the inhibitor contained no other known proteinase inhibitors. It was found that a 1:1 complex is formed and that the reaction proceeds as a second order, one step process, the association rate constant of which is 4.5 106 M−1 S−1 at pH 8.4, 37° C and 3.0 106 M−1 S−1 at pH 7.3, 37° C. The binding is very tight, the dissociation constant of the inhibitor-urokinase complex was estimated to be Ki≦10−11 M.

Keywords

Placental inhibitor of fibrinolysis - Urokinase - Reaction kinetics
 

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