Characterization of Shiga toxin-producing Escherichia coli (STEC) isolated from cases of diarrhea and Hemolytic-Uremic sSyndrome (HUS) in Brazil between the years 2007 and 2014

• Grant number: 14/21064-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2015
• End date: January 31, 2016
• Field of knowledge: Health Sciences - Collective Health - Public Health
• Principal Investigator: Rodrigo Tavanelli Hernandes
• Grantee: Samara Louzada Oliveira
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Shiga toxin-producing Escherichia coli (STEC) strains are among the most notorious E. coli diarrheagenic pathotype because its wide geographic distribution, severity of clinical syndromes that can cause and the various forms of transmission. The production of the Shiga-toxins (Stx) can be regarded as the main feature of the STEC pathogenesis. These bacterial exotoxins are dotted with at least three different biological activities: cytotoxicity, enterotoxicity and neurotoxicity. However, the majority of the STEC strains can harbor additional virulence factors which can contribute to a worse prognostic in human infections. Among these factors can be mentioned: the STEC/EHEC hemolysin, the pathogenicity island LEE (Locus of Enterocyte Effacemen), the SubAB cytotoxin (subtilase), the cytolethal distending toxin (CDT-V), several fimbrial and afimbrial adhesins and autotransporter proteins. The main objective of the this study is to analyze STEC strains, isolated in Brazil in the period between 2007 and 2014 from diarrhea cases and hemolytic uremic syndrome, regarding to their ability of Stx production, the expression of the hemolytic phenotype, ability to interact with cultivated epithelial cells and the presence of several genes related to toxins, adhesins and autotransporter proteins.