Structural studies of phospholipases A2 myotoxic of bothropic venom complexed with inhibitor and optimization of new crystallographic methodologies

• Grant number: 13/00873-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: May 01, 2013
• End date: February 28, 2017
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Marcos Roberto de Mattos Fontes
• Grantee: Rafael Junqueira Borges
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated scholarship(s): 14/11182-5 - Structural studies of phospholipases A2 myotoxic of bothropic venom complexed with inhibitor and optimization of new crystallographic methodologies, BE.EP.DR

Abstract

The great majority of ophidian accidents in Brazil are caused by Bothrops genus snakes. Myonecrosis, which is not well neutralized by administration of antiophidian serum, is one of the consequences of these accidents. The vaster protein component of bothropic venom and one of the main responsibles for muscular necrosis is the phospholipases A2 myotoxic (PLA2s). These toxins may be classified in PLA2s or Asp49-PLA2s, whose myotoxic mechanism in the envenoming is related to the catalytic process, and in homologue PLA2s or Lys49-PLA2s, whose structure is similar to PLA2s, although myotoxic mechanism is not related to catalysis and is not well known. On the other hand, some Asp49-PLA2s share the characteristic of homologue PLA2s to exert myotoxic independent of catalysis. Thus, the objective of this project is to understand this mechanism, the myotoxic independent of catalysis, by studies of the bothropic myotoxins BthTX-II e PrTX-III (two basic Asp-PLA2s) and BthTX-I (homologue PLA2) in native and complexed states. To achieve it, we will perform structural studies (X-ray crystallography and Small-angle X-ray scattering) and theoretical (Normal mode molecular dynamics). Beyond that, the generated models and data will be used to extend the scope of the novel ab initio crystallographic method, ARCIMBOLDO, to test and optimize it in the scenario of using different models from normal mode molecular dynamics and exploting structural units different from the currently used secondary structure elements. In summary, the results of this project intend to aid myotoxic mechanism comprehension and the complementation of antiofidian serum with the inhibitors studied, or posteriorly with drug design, and optimize the ab initio method to other crystallographic determinations.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BORGES, RAFAEL J.; CARDOSO, FABIO F.; FERNANDES, CARLOS A. H.; DREYER, THIAGO R.; DE MORAES, DELKIA S.; FLORIANO, RAFAEL S.; RODRIGUES-SIMIONI, LEA; FONTES, MARCOS R. M.. Functional and structural studies of a Phospholipase A(2)-like protein complexed to zinc ions: Insights on its myotoxicity and inhibition mechanism. BIOCHIMICA ET BIOPHYSICA ACTA-GENERAL SUBJECTS, v. 1861, n. 1, p. 11-pg., 2017-01-01. (15/17286-0, 13/00873-4)

BORGES, RAFAEL J.; CARDOSO, FABIO F.; FERNANDES, CARLOS A. H.; DREYER, THIAGO R.; DE MORAES, DELKIA S.; FLORIANO, RAFAEL S.; RODRIGUES-SIMIONI, LEA; FONTES, MARCOS R. M.. Functional and structural studies of a Phospholipase A(2)-like protein complexed to zinc ions: Insights on its myotoxicity and inhibition mechanism. BIOCHIMICA ET BIOPHYSICA ACTA-GENERAL SUBJECTS, v. 1861, n. 1, A, p. 3199-3209, JAN 2017. (13/00873-4, 15/17286-0)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

BORGES, Rafael Junqueira. Structural studies of PLA2-like toxins and development of the structure solution method sequence slider. 2017. Doctoral Thesis - Universidade Estadual Paulista (Unesp). Instituto de Biociências. Botucatu Botucatu.