Open AccessCharacterization of Shiga toxin‐producing Escherichia coli isolated from aquatic environments
Author(s) -
GarcíaAljaro C.,
Muniesa M.,
Blanco J.E.,
Blanco M.,
Blanco J.,
Jofre J.,
Blanch A.R.
Publication year - 2005
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/j.femsle.2005.03.038
Subject(s) - microbiology and biotechnology , shiga toxin , biology , intimin , escherichia coli , virulence , serotype , bacterial adhesin , stx2 , shiga like toxin , gene , genotype , virology , enterobacteriaceae , genetics
This study reports the phenotypic and genotypic characterization of 144 Shiga toxin‐producing Escherichia coli (STEC) strains isolated from urban sewage and animal wastewaters using a Shiga toxin 2 gene variant ( stx 2 )‐specific DNA colony hybridization method. All the strains were classified as E. coli and belonged to 34 different serotypes, some of which had not been previously reported to carry the stx 2 genes (O8:H31, O89:H19, O166:H21 and O181:H20). Five stx 2 subtypes ( stx 2 , stx 2 c , stx 2 d , stx 2 e and stx 2 g ) were detected. The stx 2 , stx 2 c , stx 2 d and stx 2 e subtypes were present in urban sewage and stx 2 e was the only stx 2 subtype found in pig wastewater samples. The stx 2 c and stx 2 g were more associated with cattle wastewater. One strain was positive for the intimin gene ( eae ) and five strains of serotypes were positive for the adhesin encoded by the saa gene. A total of 41 different seropathotypes were found. On the basis of occurrence of virulence genes, most non‐O157 STEC strains are assumed to be low‐virulence serotypes.