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Updated: Jul 6, 2026
08:01
The Nijmegen Hemostasis Assay: Simultaneous Fluorogenic Measurement of Thrombin and Plasmin Generation in a Single Well
Published on: February 27, 2026
Thrombin
1Department of Biochemistry and Molecular Biophysics, Washington University Medical School, St. Louis, MO 63110, United States. enrico@wustl.edu
Molecular Aspects of Medicine
|March 11, 2008
Summary
Sodium ions (Na+) activate thrombin, a key enzyme in blood clotting, influencing its procoagulant functions. Understanding thrombin
Area of Science:
- Biochemistry
- Molecular Biology
- Enzymology
Background:
- Thrombin, a serine protease, has dual roles in blood coagulation, acting as both procoagulant and anticoagulant.
- Sodium ion (Na+) binding is crucial for thrombin's procoagulant and signaling activities, but not for cleaving protein C.
Purpose of the Study:
- To review the molecular basis of thrombin function and its allosteric regulation.
- To elucidate the structural and kinetic mechanisms underlying thrombin's distinct functional states.
Main Methods:
- Structural analysis of thrombin.
- Mutagenesis studies.
- Kinetic investigations.
Main Results:
- Thrombin exists in three interconvertible forms: E*, E, and E:Na+.
- Na+ binding significantly alters thrombin's structure and activity, transitioning it from a slow to a fast form.
- The inactive E* form is unable to bind Na+ or substrates.
Conclusions:
- Thrombin's function is regulated by ligand binding to distinct domains, showcasing its molecular plasticity.
- Thrombin serves as a prototypic allosteric serine protease and a model system for enzyme analysis.
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