American Society of Hirudotherapy

Molecular mechanisms of thrombin function

Review published in Cellular and molecular life sciences : CMLS (1997)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Narrative reviewDrug DevelopmentSalivary PharmacologyDi Cera et al. · Cellular and molecular life sciences : CMLS, 1997

Abstract

The discovery of thrombin as a Na(+)-dependent allosteric enzyme has revealed a novel strategy for regulating protease activity and specificity. The alllosteric nature of this enzyme influences all its physiologically important interactions and rationalizes a large body of structural and functional information. For the first time, a coherent mechanistic framework is available for understanding how thrombin interacts with fibrinogen, thrombomodulin and protein C, and how Na+ binding influences the specificity sites of the enzyme. This information can be used for engineering thrombin mutants with selective specificity towards protein C and for the rational design of potent active site inhibitors. Thrombin also serves as a paradigm for allosteric proteases. Elucidation of the molecular basis of the Na(+)-dependent allosteric regulation of catalytic activity, based on the residue present at position 225, provides unprecedented insights into the function and evolution of serine proteases. This mechanism represents one of the simplest and most important structure-function correlations ever reported for enzymes in general. All vitamin K-dependent proteases and some complement factors are subject to the Na(+)-dependent regulation discovered for thrombin. Na+ is therefore a key factor in the activation of zymogens in the coagulation and complement systems.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.Review
Indexed MeSH termsAllosteric RegulationAnimalsAntithrombinsBlood CoagulationFibrinogenHirudinsHumansModels, MolecularProtein CProtein ConformationSodiumSubstrate SpecificityThermodynamicsThrombinThrombomodulin

Summary

This paper explains thrombin's Na+-dependent allosteric regulation, showing how Na+ binding shapes interactions with fibrinogen, thrombomodulin, and protein C, informs engineering of protein C-selective mutants and active-site inhibitors, and extends to all vitamin K-dependent proteases and some complement factors.

Context

This review summarizes thrombin's molecular mechanisms as a Na+-dependent allosteric enzyme, describing how Na+ binding influences specificity toward fibrinogen, thrombomodulin, and protein C, and how this framework may support engineering of thrombin mutants and active-site inhibitors. It also places thrombin within broader serine protease evolution and coagulation/complement regulation. The abstract does not mention hirudin, leeches, leech-derived compounds, or hirudotherapy.

Citation

Reference (Vancouver style)

Di Cera E, Dang QD, Ayala YM. Molecular mechanisms of thrombin function. Cell Mol Life Sci. 1997;53(9):701-730. doi:10.1007/s000180050091. PMID: 9368668

Bibliographic details (authors, volume, pages, DOI) are taken from the PubMed record.

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