NMR-based structural characterization of a two-disulfide-bonded analogue of the FXIIIa inhibitor tridegin
Structural biology published in International Journal of Molecular Sciences (2021)
Abstract
The saliva of blood-sucking leeches contains a plethora of anticoagulant substances. One of these compounds derived from Haementeria ghilianii, the 66mer three-disulfide-bonded peptide tridegin, specifically inhibits the blood coagulation factor FXIIIa. Tridegin represents a potential tool for antithrombotic and thrombolytic therapy. We recently synthesized two-disulfide-bonded tridegin variants, which retained their inhibitory potential. For further lead optimization, however, structure information is required. We thus analyzed the structure of a two-disulfide-bonded tridegin isomer by solution 2D NMR spectroscopy in a combinatory approach with subsequent MD simulations. The isomer was studied using two fragments, i.e., the disulfide-bonded N-terminal (Lys1-Cys37) and the flexible C-terminal part (Arg38-Glu66), which allowed for a simplified, label-free NMR-structure elucidation of the 66mer peptide. The structural information was subsequently used in molecular modeling and docking studies to provide insights into the structure-activity relationships. The present study will prospectively support the development of anticoagulant-therapy-relevant compounds targeting FXIIIa.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
NMR structural characterization of two-disulfide tridegin variants reveals key folds for FXIIIa inhibition — insights for next-generation leech-derived inhibitor design.
Why This Matters for Hirudotherapy
This study reports the solution NMR structure of a two-disulfide-bonded analogue of tridegin, a 66-mer peptide from the leech Haementeria ghilianii that specifically inhibits blood coagulation factor FXIIIa, using a two-fragment approach combined with molecular dynamics simulations. The work matters for hirudotherapy and the leech secretome because it advances lead optimization of a leech-derived antithrombotic/thrombolytic candidate toward potential therapeutic development targeting FXIIIa. The structural data support molecular modeling and docking studies aimed at understanding structure-activity relationships. The honest caveat is that this is a preclinical biophysical study; it involves no animal or human subjects, no leech therapy, and the therapeutic relevance is prospective—the abstract does not claim clinical efficacy or FDA approval.
Citation
NMR-based structural characterization of a two-disulfide-bonded analogue of the FXIIIa inhibitor tridegin.
Schmitz T et al. · International journal of molecular sciences, 2021
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