American Society of Hirudotherapy

Crystallization and preliminary crystallographic analysis of antistasin, a leech-derived inhibitor of blood coagulation factor Xa

Research article published in Journal of molecular biology (1993)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: In vitro / laboratoryDrug DevelopmentSchreuder H et al. · Journal of molecular biology, 1993

Abstract

The salivary gland of the Mexican leech Haementeria officinalis contains a 15 kDa protein which is a potent and selective inhibitor of factor Xa. It inhibits not only blood coagulation, but also metastasis. A gene, coding for a sequence similar to published antistasin sequences, has been synthesized and expressed in Chinese hamster ovary (CHO) cells. The recombinant protein was purified and crystallized at pH 6.0, using 31% ammonium sulfate as a precipitant. The crystals diffract at least to 2.8 A. The spacegroup is I422 with a = b = 77.7 A and c = 88.4 A. The crystals contain 42% solvent and one protein molecule in the asymmetric unit. A search for heavy atom derivatives is in progress.

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't
Indexed MeSH termsAnimalsCHO CellsCricetinaeCrystallizationFactor Xa InhibitorsInvertebrate HormonesLeechesRecombinant ProteinsX-Ray Diffraction

Summary

Crystallization and preliminary crystallographic analysis of antistasin, a leech-derived inhibitor of blood coagulation factor Xa.

Why This Matters for Hirudotherapy

This article reports the crystallization and preliminary X-ray diffraction analysis of a ~15 kDa factor Xa inhibitor from the Mexican leech Haementeria officinalis, expressed recombinantly in CHO cells from a gene coding for a sequence similar to published antistasin sequences. The abstract notes that the protein inhibits both blood coagulation and metastasis, and describes crystals diffracting to at least 2.8 Å in space group I422, with heavy-atom derivative searches underway. This is relevant to ASH as early structural work on a leech-derived antithrombotic protein. Caveat: the work reported is limited to crystallization and preliminary diffraction analysis, with no new functional, in vivo, or clinical data.

Citation

Crystallization and preliminary crystallographic analysis of antistasin, a leech-derived inhibitor of blood coagulation factor Xa

Schreuder H et al. · Journal of molecular biology, 1993

DOI

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

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