Phenotypic and Genotypic Characterization of Avian Escherichia coli O86:K61 Isolates Possessing a Gamma-Like Intimin
AUTOR(ES)
La Ragione, R. M.
FONTE
American Society for Microbiology
RESUMO
Escherichia coli O86:K61 has long been associated with outbreaks of infantile diarrhea in humans and with diarrheal disease in many animal species. Studies in the late 1990s identified E. coli O86:K61 as the cause of mortality in a variety of wild birds, and in this study, 34 E. coli O86:K61 isolates were examined. All of the isolates were nonmotile, but most elaborated at least two morphologically distinct surface appendages that were confirmed to be type 1 and curli fimbriae. Thirty-three isolates were positive for the eaeA gene encoding a gamma type of intimin. No phenotypic or genotypic evidence was obtained for elaboration of Shiga-like toxins, but most isolates possessed the gene coding for the cytolethal distending toxin. Five isolates were selected for adherence assays performed with tissue explants and HEp-2 cells, and four of these strains produced attaching and effacing lesions on HEp-2 cells and invaded the cells, as determined by transmission electron microscopy. Two of the five isolates were inoculated orally into 1-day-old specific-pathogen-free chicks, and both of these isolates colonized, invaded, and persisted well in this model. Neither isolate produced attaching and effacing lesions in chicks, although some pathology was evident in the alimentary tract. No deaths were recorded in inoculated chicks. These findings are discussed in light of the possibility that wild birds are potential zoonotic reservoirs of attaching and effacing E. coli.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=126447Documentos Relacionados
- Purification and characterization of a gamma-like DNA polymerase from Chenopodium album L.
- Genotypic and phenotypic characterization of Escherichia coli isolates from dogs manifesting attaching and effacing lesions.
- Phenotypic and genotypic characterization of Salmonella enteritidis isolates
- Phenotypic and genotypic characterization of enterotoxigenic Escherichia coli serotype O8:KX105 and O8:K"2829" strains isolated from piglets with diarrhea.
- Phenotypic and Genotypic Characterization of Mycobacterium africanum Isolates from West Africa