Purification and characterization of a novel anti-coagulant from the leech Hirudinaria manillensis
Research article published in Zool Res (2019)
Abstract
Protease inhibitors have been reported rarely from the leech Hirudinaria manillensis. In this study, we purified a novel protease inhibitor (bdellin-HM-2) with anticoagulant properties from H. manillensis. With a molecular weight of 1.4x104, bdellin-HM-2 was also characterized with three intra-molecular disulfide bridges at the N-terminus and multiple HHXDD and HXDD motifs at the C-terminus. cDNA cloning revealed that the putative nucleotide-encoding protein of bdellin-HM-2 contained 132 amino acids and was encoded by a 399 bp open reading frame (ORF). Sequence alignment showed that bdellin-HM-2 shared similarity with the "non-classical" Kazal-type serine protease inhibitors, but had no inhibitory effect on trypsin, elastase, chymotrypsin, kallikrein, factor XIIa (FXIIa), factor XIa (FXIa), factor Xa (FXa), thrombin, or plasmin. Bdellin-HM-2 showed anticoagulant effects by prolonging the activated partial thromboplastin time (aPTT), indicating a role in enabling H. manillensis to obtain a blood meal from its host. Our results suggest that bdellin-HM-2 may play a crucial role in blood-sucking in this leech species and may be a potential candidate for the development of clinical anti-thrombotic drugs.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Protease inhibitors have been reported rarely from the leech. In this study, we purified a novel protease inhibitor (bdellin-HM-2) with anticoagulant properties from.
Why This Matters for Hirudotherapy
This study reports the purification and biochemical characterization of bdellin-HM-2, a novel anticoagulant protease inhibitor (molecular weight ~14 kDa) isolated from the leech Hirudinaria manillensis. Bdellin-HM-2 shares similarity with non-classical Kazal-type serine protease inhibitors, showed no inhibitory effect on multiple tested proteases including thrombin, and demonstrated anticoagulant effects by prolonging activated partial thromboplastin time (aPTT), suggesting a role in facilitating blood-feeding by this leech species. This work is directly relevant to ASH's domain, as it characterizes a component of the leech secretome with the authors suggesting potential as a candidate for anti-thrombotic drug development. However, this is a preclinical biochemical study with no clinical or in-vivo therapeutic data presented.
Citation
Purification and characterization of a novel anti-coagulant from the leech Hirudinaria manillensis.
Cheng RM et al. · Zool Res, 2019
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