Structural and binding studies of a C-type galactose-binding lectin from Bothrops jararacussu snake venom

Autor(es)

Sartim, Marco A. ; Pinheiro, Matheus P. ; de Padua, Ricardo A. P. ; Sampaio, Suely V. ; Cristina Nonato, M.

• Tipo de documento: Artigo Científico
• Fonte: Toxicon; v. 126, p. 59-69, FEB 2017.
• Citações Web of Science: 6

Resumo

BJcuL is a snake venom galactoside-binding lectin (SVgalL) isolated from Bothrops jararacussu and is involved in a wide variety of biological activities including triggering of pro-inflammatory response, disruption of microbial biofilm structure and induction of apoptosis. In the present work, we determined the crystallographic structure of BJcuL, the first holo structure of a SVgalL, and introduced the fluorescence-based thermal stability assay (Thermofluor) as a tool for screening and characterization of the binding mechanism of SVgalL ligands. BJcuL structure revealed the existence of a porous and flexible decameric arrangement composed of disulfide-linked dimers related by a five-fold symmetry. Each monomer contains the canonical carbohydrate recognition domain, a calcium ion required for BJcuL lectinic activity and a sodium ion required for protein stabilization. BJcuL thermostability was found to be induced by calcium ion and galactoside sugars which exhibit hyperbolic saturation profiles dependent on ligand concentration. Serendipitously, the gentamicin group of aminoglycoside antibiotics (gAGAs) was also identified as BJcuL ligands. On contrast, gAGAs exhibited a sigmoidal saturation profile compatible with a cooperative mechanism of binding. Thermofluor, hemagglutination inhibition assay and molecular docking strategies were used to identify a distinct binding site in BJcuL localized at the dimeric interface near the fully conserved intermolecular Cys86-Cys86 disulfide bond. The hybrid approach used in the present work provided novel insights into structural behavior and functional diversification of SVgaLs. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 11/23236-4 - Toxinas animais nativas e recombinantes: análise funcional, estrutural e molecular
• Beneficiário: Suely Vilela
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 14/19127-3 - Efeito da LAAO de Calloselasma rhodostoma e Bothrops moojeni na maquinaria apoptótica de linhagens JAK2V617F positivas de neoplasias mieloproliferativas
• Beneficiário: Thaís Fontanezi Maciel
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 14/11266-4 - Caracterização estrutural e biofísica de toxinas animais
• Beneficiário: Ricardo Augusto Pereira de Pádua
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado