HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Longstaff, C. Articles by Gaffney, P. J. Search for Related Content PubMed PubMed Citation Articles by Longstaff, C. Articles by Gaffney, P. J. Social Bookmarking                      What's this?

J. Biol. Chem., Vol. 267, Issue 1, 173-179, 01, 1992

Kinetics of plasmin activation of single chain urinary-type plasminogen activator (scu-PA) and demonstration of a high affinity interaction between scu-PA and plasminogen

C Longstaff, AM Clough and PJ Gaffney
Division of Haematology, National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, United Kingdom.

The activation kinetics of single chain urinary-type plasminogen activator (scu-PA) by plasmin have been studied in detail. Nonstandard Michaelis-Menten kinetics were observed. To explain our results, we propose a model in which plasmin can exist in two conformations of lower activity (kcat/Km = 1.4 x 10(6) M-1 s-1) or higher activity (kcat/Km = 16.7 x 10(6) M-1 s-1) depending on whether a lysine binding site is occupied or free, respectively. These kinetic studies demonstrate that scu-PA interacts at this binding site (KD approximately 30 nM) and so is able to act as both a substrate and effector in this reaction. Binding was also demonstrated between scu-PA and Glu- or Lys-plasminogen at a high affinity site (KD approximately 65 nM), sensitive to the presence of lysine analogs. This suggests that scu-PA may be almost completely bound to plasminogen in plasma under normal physiological conditions and provides a possible explanation for the fibrin specificity of this activator, as discussed.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				A. A. Eddy Plasminogen activator inhibitor-1 and the kidney Am J Physiol Renal Physiol, August 1, 2002; 283(2): F209 - F220. [Abstract] [Full Text] [PDF]

				C. Longstaff, R. E. Merton, P. Fabregas, and J. Felez Characterization of Cell-Associated Plasminogen Activation Catalyzed by Urokinase-Type Plasminogen Activator, but Independent of Urokinase Receptor (uPAR, CD87) Blood, June 1, 1999; 93(11): 3839 - 3846. [Abstract] [Full Text] [PDF]

				V. Sinniger, R. E. Merton, P. Fabregas, J. Felez, and C. Longstaff Regulation of Tissue Plasminogen Activator Activity by Cells. DOMAINS RESPONSIBLE FOR BINDING AND MECHANISM OF STIMULATION J. Biol. Chem., April 30, 1999; 274(18): 12414 - 12422. [Abstract] [Full Text] [PDF]

				P. E. Bock, D. E. Day, I. M. A. Verhamme, M. M. Bernardo, S. T. Olson, and J. D. Shore Analogs of Human Plasminogen That Are Labeled with Fluorescence Probes at the Catalytic Site of the Zymogen J. Biol. Chem., January 12, 1996; 271(2): 1072 - 1080. [Abstract] [Full Text] [PDF]