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Genes from the medicinal leech Hirudo medicinalis coding for unusual enzymes that specifically cleave endo-epsilon (gamma-Glu)-Lys isopeptide bonds and help to dissolve blood clots

Research article published in Molecular & general genetics (1996)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: In vitro / laboratoryDrug DevelopmentZavalova LL et al. · Molecular & general genetics, 1996

Abstract

We previously detected in salivary gland secretions of the medicinal leech (Hirudo medicinalis) a novel enzymatic activity, endo-epsilon(gamma-Glu)-Lys isopeptidase, which cleaves isopeptide bonds formed by transglutaminase (Factor XIIIa) between glutamine gamma-carboxamide and the epsilon-amino group of lysine. Such isopeptide bonds, either within or between protein polypeptide chains are formed in many biological processes. However, before we started our work no enzymes were known to be capable of specifically splitting isopeptide bonds in proteins. The isopeptidase activity we detected was specific for isopeptide bonds. The enzyme was termed destabilase. Here we report the first purification of destabilase, part of its amino acid sequence isolation and sequencing of two related cDNAs derived from the gene family that encodes destabilase proteins, and the detection of isopeptidase activity encoded by one of these cDNAs cloned in a baculovirus expression vector. The deduced mature protein products of these cDNAs contain 115 and 116 amino acid residues, including 14 highly conserved Cys residues, and are formed from precursors containing specific leader peptides. No homologous sequences were found in public databases.

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 termsAmino Acid SequenceAnimalsBase SequenceCell LineChromatography, Ion ExchangeCloning, MolecularDNA, ComplementaryEndopeptidasesHydrolysisLeechesMolecular Sequence DataPeptidesProtein Structure, SecondaryRecombinant ProteinsSequence Homology, Amino AcidSpodoptera

Summary

Purifying the isopeptidase destabilase from medicinal leech (Hirudo medicinalis) saliva, the authors sequenced two related cDNAs encoding 115- and 116-residue proteins with 14 conserved cysteines, and demonstrated isopeptidase activity from one clone.

Why This Matters for Hirudotherapy

This study reports the purification and molecular characterization of destabilase, a novel enzyme from Hirudo medicinalis salivary gland secretions that specifically cleaves endo-epsilon(gamma-Glu)-Lys isopeptide bonds formed by transglutaminase (Factor XIIIa). The authors purified the enzyme, determined partial amino acid sequence, isolated two related cDNAs encoding mature proteins of 115 and 116 residues with 14 conserved Cys residues, and confirmed isopeptidase activity from one cloned cDNA in a baculovirus expression system; no homologous sequences were found in public databases. The study characterizes a distinct enzyme from the medicinal leech that targets isopeptide bonds formed in biological processes. The work is biochemical in nature—purification and molecular cloning—and the abstract does not report in vivo efficacy, clinical data, or specify which biological processes are affected.

Citation

Reference (Vancouver style)

Zavalova L, Lukyanov S, Baskova I, Snezhkov E, Akopov S, Berezhnoy S, et al. Genes from the medicinal leech Hirudo medicinalis coding for unusual enzymes that specifically cleave endo-epsilon (gamma-Glu)-Lys isopeptide bonds and help to dissolve blood clots. Mol Gen Genet. 1996;253(1-2):20-25. doi:10.1007/s004380050291. PMID: 9003282

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

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