The role of rpoS on the pathogenicity of enterotoxigenic Escherichia coli

• Grant number: 13/05931-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): June 01, 2013
• Effective date (End): November 30, 2014
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Beny Spira
• Grantee: Talita de Sousa Laurentino
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Enterotoxigenic Escherichia coli (ETEC) is one of the main causes of diarrhea. Its mechanism of virulence consists of adhesion to intestinal epithelium and release of toxins. Some environments pose a challenge for E. coli growth or survival, to which the bacterium responds by expressing genes that help protecting against environmental stresses. The most important of this genes is rpoS, responsible for the general stress responses. Mutations in rpoS or in one of the genes that regulate its expression are not uncommon in natural E. coli isolates. These mutations can also affect the bacteria's virulence. In this study we will investigate the effect of rpoS inactivation on ETEC virulence. An rpoS deletion will be constructed in the prototype strain H10407 by allelic recombination. The production of LT and the adherence of ETEC to epithelial cells will be tested. (AU)