Американское общество гирудотерапии

Crystal structure of anticoagulant thrombin variant E217K provides insights into thrombin allostery.

Research article published in The Journal of biological chemistry (2004)

Последнее обновление: June 18, 2026Рецензент: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportРазработка лекарственных препаратовФармакология секрета слюнных желёзCarter et al. · The Journal of biological chemistry, 2004

Abstract

Thrombin is the ultimate protease of the blood clotting cascade and plays a major role in its own regulation. The ability of thrombin to exhibit both pro- and anti-coagulant properties has spawned efforts to turn thrombin into an anticoagulant for therapeutic purposes. This quest culminated in the identification of the E217K variant through scanning and saturation mutagenesis. The antithrombotic properties of E217K thrombin are derived from its inability to convert fibrinogen to a fibrin clot while maintaining its thrombomodulin-dependent ability to activate the anticoagulant protein C pathway. Here we describe the 2.5-A crystal structure of human E217K thrombin, which displays a dramatic restructuring of the geometry of the active site. Of particular interest is the repositioning of Glu-192, which hydrogen bonds to the catalytic Ser-195 and which results in the complete occlusion of the active site and the destruction of the oxyanion hole. Substrate binding pockets are further blocked by residues previously implicated in thrombin allostery. We have concluded that the E217K mutation causes the allosteric inactivation of thrombin by destabilizing the Na(+) binding site and that the structure thus may represent the Na(+)-free, catalytically inert "slow" form.

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.
Indexed MeSH termsAllosteric SiteBinding SitesCatalysisCrystallography, X-RayHumansHydrogen BondingModels, MolecularMutagenesis, Site-DirectedProtein BindingProtein ConformationSodiumThrombin

Резюме

Thrombin is the ultimate protease of the blood clotting cascade and plays a major role in its own regulation. The ability of thrombin to exhibit both pro- and anti-coagulant properties has spawned efforts to turn thrombin into an anticoagulant for therapeutic purposes.

Почему это важно для гирудотерапии

This study determined the 2.5 Å crystal structure of the anticoagulant thrombin variant E217K, revealing dramatic active-site restructuring including Glu-192 repositioning that hydrogen bonds to catalytic Ser-195, resulting in complete occlusion of the active site and destruction of the oxyanion hole. The authors conclude that the E217K mutation causes allosteric inactivation of thrombin by destabilizing the Na+ binding site and that the structure may represent the Na+-free, catalytically inert 'slow' form. The work provides structural insight into thrombin allostery relevant to anticoagulant design. CAVEAT: No hirudin, leech-derived compounds, or hirudotherapy are mentioned in the abstract; the connection to ASH's domain is entirely indirect through thrombin structural biology, and no defensible leech link exists.

Цитирование

Crystal structure of anticoagulant thrombin variant E217K provides insights into thrombin allostery.

Carter et al. · The Journal of biological chemistry, 2004

Связанный клинический контекст

Добавлено в библиотеку ASH: May 28, 2026 · Последнее обновление сайта: June 18, 2026

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