Crotacetin, a novel snake venom c-type lectin, is homolog of convulxin

Snake venom (sv) C-type lectins encompass a group of hemorrhagic toxins, which are able to interfere with hemostasis. They share significant similarity in their primary structures with C-type lectins of other animals, and also present a conserved carbohydrate recognition domain (CRD). A very well st...

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Bibliographic Details
Authors: Rádis-Baptista, Gandhi, Moreno, F. B. M. B., Nogueira, L. L., Martins, A. M. C., Tomaya, D. O, Tomaya, M. H, Azevedo Júnior, W. F., Cavada, B. S., Yamane, T.
Format: article
Status:Published version
Publication Date:2005
Country:Brasil
Institution:Universidade Federal do Ceará (UFC)
Repository:Repositório Institucional da Universidade Federal do Ceará (UFC)
Language:English
OAI Identifier:oai:repositorio.ufc.br:riufc/59787
Online Access:http://www.repositorio.ufc.br/handle/riufc/59787
Access Level:Open access
Keyword:Cobra
Veneno
Antimicrobianos
Description
Summary:Snake venom (sv) C-type lectins encompass a group of hemorrhagic toxins, which are able to interfere with hemostasis. They share significant similarity in their primary structures with C-type lectins of other animals, and also present a conserved carbohydrate recognition domain (CRD). A very well studied sv C-type lectin is the heterodimeric toxin, convulxin (CVX), from the venoms of South American rattlesnakes, Crotalus durissus terrificus and C. d. cascavella. It consists of two subunits, alfa (CVXα, 13.9 kDa) and beta (CVXβ, 12.6 kDa), joined by inter and intra-chain disulfide bounds, and is arranged in a tetrameric α4β4 conformation. Convulxin is able to activate platelet and induce their aggregation by acting via p62/GPVI collagen receptor. Several cDNA precursors, homolog of CVX subunits, were cloned by PCR homology screening. As determined by computational analysis, one of them, named crotacetin β subunit, was predicted as a polypeptide with a tridimensional conformation very similar to other subunits of convulxin-like snake toxins. Crotacetin was purified from C. durissus venoms by gel permeation and reverse phase high performance liquid chromatography. The heterodimeric crotacetin is expressed in the venoms of several C. durissus subspecies, but it is prevalent in the venom of C. durissus cascavella. As inferred from homology modeling, crotacetin induces platelet aggregation but noticeably exhibits antimicrobial activity against Gram-positive and Gram-negative bacteria