Primary structure and function of novel O-glycosylated hirudins from the leech Hirudinaria manillensis.
Comparative study published in Biochemistry (1992)
Abstract
Hirudin from the leech Hirudo medicinalis is a most powerful anticoagulant, and many isoforms have been described. In the present work, the primary structure of two hirudins from the leech Hirudinaria manillensis has been elucidated. The antithrombotic activity is similar to that of H. medicinalis hirudins although the sequence identity is below 60%. Surprisingly, the hirudins were found to be glycosylated at one site. Sugar analysis after methanolysis yielded fucose, galactose, and N-acetylgalactosamine. These results combined with data from matrix-assisted laser desorption ionization mass spectrometry, plasma desorption mass spectrometry, capillary zone electrophoresis, and lectin-binding tests indicate that the sequence is Fuc-Gal beta 1-3GalNAc-(O-threonine). This structure shows an interesting similarity to human blood group H determinants.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Hirudin from the leech Hirudo medicinalis is a most powerful anticoagulant, and many isoforms have been described. In the present work, the primary structure of two hirudins from the leech Hirudinaria manillensis has been elucidated.
Why This Matters for Hirudotherapy
This study elucidated the primary structure of two hirudins from the leech Hirudinaria manillensis, reporting antithrombotic activity similar to Hirudo medicinalis hirudins despite less than 60% sequence identity, and identifying a novel O-glycosylation site (Fuc-Galβ1-3GalNAc-O-threonine) with structural similarity to human blood group H determinants. For ASH and hirudotherapy, the work is directly relevant because it characterizes new leech-derived anticoagulant molecules, expanding knowledge of the molecular diversity present within the leech secretome across different medicinal leech species. The unexpected glycosylation is scientifically notable because such modifications can influence stability, pharmacokinetics, or immunogenicity of anticoagulants. An honest caveat is that this is a biochemical and structural characterization reporting antithrombotic activity; it does not establish clinical efficacy, in vivo performance, or the specific target/mechanism of these hirudins.
Citation
Primary structure and function of novel O-glycosylated hirudins from the leech Hirudinaria manillensis.
Steiner V et al. · Biochemistry, 1992
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