Characterization of ETT2 (Escherichia coli type III secretion system 2) of enteroaggregative E. coli

• Grant number: 15/15135-4
• Support Opportunities: Regular Research Grants
• Start date: December 01, 2015
• End date: November 30, 2017
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Waldir Pereira Elias Junior
• Grantee: Waldir Pereira Elias Junior
• Host Institution: Instituto Butantan. São Paulo , SP, Brazil
• City of the host institution: São Paulo
• Associated researchers: Cecilia Mari Abe ; Martha Harumi Sonobe ; Roberto Nepomuceno de Souza Lima
• Associated research grant(s): 16/50479-9 - Molecular and structural characterization of ETT-2 (Escherichia coli type III secretion system 2) of enteroaggregative E. coli, AP.R SPRINT

Abstract

Enteroaggregative Escherichia coli (EAEC) is an emerging pathogen associated with cases of diarrhea in children and adults, in both developing and developed countries. In Brazil, EAEC has been systematically found as the most prevalent diarrheagenic E. coli pathotype. This pathotype is very heterogeneous regarding the presence of putative virulence factors, indicating a multifactorial profile to cause disease. Analysis of the genome of EAEC prototype strain (042, serotype O44:H18) indicated the presence of genes encoding a type III secretion system (T3SS) which, in other pathogens, is associated with the translocation of effectors proteins directly into the cytoplasm of eukaryotic cells. This system, called ETT2 (Escherichia coli type three secretion system 2), presents high similarity to that found in Salmonella enteric and enterohemorrhagic E. coli, therefore considered as a T3SS variant. In the genome of EAEC 042 all genes that comprise ETT-2 are intact, indicating their functionality. Until the present moment such activity has not been demonstrated, neither the possible transported translocators identified. Therefore, the present study has the original objective to characterize the EAEC 042 ETT-2 system, in terms of identification of proteins secreted by the system, analysis of the injectosome by electron microscopy, and determination of the prevalence of ETT-2 encoding genes in a large collection of EAEC. It is proposed to contribute to the knowledge of the pathogenesis caused by this important pathotype in our country, by identifying putative new secreted virulence factors. (AU)

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)

ANDRADE, FERNANDA B.; ABREU, AFONSO G.; NUNES, KAMILA O.; GOMES, TANIA A. T.; PIAZZA, ROXANE M. F.; ELIAS, WALDIR P.. Distribution of serine protease autotransporters of Enterobacteriaceae in typical and atypical enteroaggregative Escherichia coli. INFECTION GENETICS AND EVOLUTION, v. 50, p. 83-86, JUN 2017. (14/18286-0, 15/15135-4)