Enteroaggregative Escherichia coli from humans and animals differ in major phenotypical traits and virulence genes

Abstract

Enteroaggregative Escherichia coli (EAEC) is characterized by the expression of the aggregative adherence pattern to cultured epithelial cells. in this study, we determined the phenotypic and genotypic relationships among 86 EAEC strains of human and animal (calves, piglets and horses) feces. Serotypes and the presence of EAEC virulence markers were determined, and these results were associated with ribotyping. Strains harboring aggR (typical EAEC) of human origin were found carrying several of the searched markers, while atypical EAEC harbored none or a few markers. the strains of animal origin were classified as atypical EAEC (strains lacking aggR) and harbored only irp2 or shf. Strains from humans and animals belonged to several different serotypes, although none of them prevailed. Sixteen ribotypes were determined, and there was no association with virulence genes profiles or serotypes. Relationship was not found among the strains of this study, and the assessed animals may not represent a reservoir of human pathogenic typical EAEC.Inst Butantan, Bacteriol Lab, BR-05503900 São Paulo, BrazilInst Adolfo Lutz Registro, Secao Bacteriol, São Paulo, BrazilFed Inst Risk Assessment, Natl Reference Lab Escherichia Coli, Berlin, GermanyUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilUniv São Paulo, Inst Ciencias Biomed, Dept Microbiol, BR-05508 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilWeb of Scienc