Suchergebnisse

Enterohaemorrhagic Escherichia coli (EHEC) and enteropathogenic E coli (EPEC) translocate, dozens of type III secretion system effectors, including the WxxxE effectors Map, EspM and EspT that activate Rho GTPases. While map, which is carried on the LEE pathogenicity island, is absolutely conserved among EPEC and EHEC strains, the prevalence of espM and espT is not known. Here we report the results of a large screen aimed at determining the prevalence of esPM and espT among clinical EPEC and EHEC isolates. the results suggest that espM, detected in 51% of the tested strains, is more commonly found in EPEC and EHEC serogroups that are linked to severe human infections. in contrast, espT was absent from all the EHEC isolates and was found in only 1.8% of the tested EPEC strains. Further characterization of the virulence gene repertoire of the espT-positive strains led to the identification of a new zeta 2 intimin variant. All the espT-positive strains but two contained the tccP gene. espT was first found in Citrobacter rodentium and later in silico in EPEC E110019, which is of particular interest as this strain was responsible for a particularly severe diarrhoeal outbreak in Finland in 1987 that affected 650 individuals in a school complex and an additional 137 associated household members. Comparing the protein sequences of EspT to that of E110019 showed a high level of conservation, with only three strains encoding EspT that differed in 6 amino acids. At present, it is not clear why espT is so rare, and what impact EspM and EspT have on EPEC and EHEC infection. ; Spanish Ministry of Education and Science ; Spanish Ministry of Health and Consumer Affairs [Fondo de Investigacion Sanitaria, Spanish Network for the Research in Infectious Diseases (REIPI) ; Autonomous Government of Galicia ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; Programa de Apoio a Nucleos de Excelencia ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; MRC ; Wellcome Trust ; Univ Santiago de Compostela, Fac Vet, Dept Microbiol & Parasitol, Lab Referencia E Coli, Lugo, Spain ; Univ London Imperial Coll Sci Technol & Med, Div Cell & Mol Biol, Ctr Mol Microbiol & Infect, London SW7 2AZ, England ; Universidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, Brazil ; Complexo Hos Xeral Calde, Unidade Microbiol Clin, Lugo, Spain ; Universidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, Brazil ; Spanish Ministry of Health and Consumer Affairs [Fondo de Investigacion Sanitaria, Spanish Network for the Research in Infectious Diseases (REIPI): RD06/0008-10181 ; Spanish Ministry of Education and Science: AGL-200802129 ; Autonomous Government of Galicia: PGIDIT065TAL26101P ; Autonomous Government of Galicia: 07MRU036261PR ; FAPESP: 08/53812-4 ; Web of Science