Novel Cysteine Protease Inhibitor Derived from the Haementeria vizottoi Leech: Recombinant Expression, Purification, and Characterization
Recombinant expression published in Toxins (2021)
Abstract
Cathepsin L (CatL) is a lysosomal cysteine protease primarily involved in the terminal degradation of intracellular and endocytosed proteins. More specifically, in humans, CatL has been implicated in cancer progression and metastasis, as well as coronary artery diseases and others. Given this, the search for potent CatL inhibitors is of great importance. In the search for new molecules to perform proteolytic activity regulation, salivary secretions from hematophagous animals have been an important source, as they present protease inhibitors that evolved to disable host proteases. Based on the transcriptome of the Haementeria vizzotoi leech, the cDNA of Cystatin-Hv was selected for this study. Cystatin-Hv was expressed in Pichia pastoris and purified by two chromatographic steps. The kinetic results using human CatL indicated that Cystatin-Hv, in its recombinant form, is a potent inhibitor of this protease, with a Ki value of 7.9 nM. Consequently, the present study describes, for the first time, the attainment and the biochemical characterization of a recombinant cystatin from leeches as a potent CatL inhibitor. While searching out for new molecules of therapeutic interest, this leech cystatin opens up possibilities for the future use of this molecule in studies involving cellular and in vivo models.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Cystatin-Hv, cloned from the transcriptome of the leech Haementeria vizzotoi, was expressed in Pichia pastoris and inhibited human cathepsin L with a Ki of 7.9 nM.
Why This Matters for Hirudotherapy
This study identified, expressed in Pichia pastoris, and biochemically characterized Cystatin-Hv, a recombinant cysteine protease inhibitor from the leech Haementeria vizzotoi transcriptome, demonstrating potent inhibition of human cathepsin L (Ki = 7.9 nM). The work is purely biochemical (recombinant expression and kinetic assay) with no cellular or in vivo data.
Citation
Reference (Vancouver style)
Linhares DDC, Faria F, Kodama RT, Amorim AMXP, Portaro FCV, Trevisan-Silva D, et al. Novel Cysteine Protease Inhibitor Derived from the Haementeria vizottoi Leech: Recombinant Expression, Purification, and Characterization. Toxins (Basel). 2021;13(12):857. doi:10.3390/toxins13120857. PMID: 34941695
Bibliographic details (authors, volume, pages, DOI) are taken from the PubMed record.
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