Regulation of Thiol-dependent proteases by nitrosylation

• Grant number: 11/05987-2
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2011
• End date: May 31, 2015
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Vitor Marcelo Silveira Bueno Brandão de Oliveira
• Grantee: Marcelo Yudi Icimoto
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Nitrosylation is currently considered an important reversible post-translational modification of Proteins. The dynamic of enzyme nitrosylation/denitrosylation is important because occurs in a time order below milliseconds, contrasting with that of enzyme catalysis (seconds). Furthermore, some enzymes acts as pivotal regulators of NO-dependent signal transduction pathways. The overall objective of this project is to improve the knowledge about regulation of enzymes by nitrosylation. We will conduct in vitro inhibition of thiol-dependents enzymes with NO donors (SNAP and SNOG) and NO generator (SIN-1) in kinetic assays using recombinant enzymes and extracts of mammal cells culture. The literature of nitrosylated enzymes is restricted only to few cystein proteases, and we propose to investigate the NO inhibition behavior under some serine- and metalloproteases, all well-know affected by thiol modifier compounds. The major peptidases under study will be: thimet oligopeptidase (TOP; Rattus norvegicus; metallopeptidase), prolyl oligopeptidase (POP; Sus scrofa; serine-peptidase) and one metacaspase (TbMCA2; Trypanossoma brucei; cisteíno peptidase).