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Investigating the Whole-Genome Sequence of a New Locus of Enterocyte Effacement-Positive Shiga Toxin-Producing Escherichia coli O157:H7 Strain Isolated from River Water.

ABSTRACT: Diverse Shiga toxin-producing Escherichia coli (STEC) strains have been isolated from several environmental samples. Rivers are associated with the distribution of STEC pathogens in the environment. Thus, we report the complete genome sequence of a locus of enterocyte effacement (LEE)-positive STEC O157:H7 strain isolated from the Mississippi River.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC7082455 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Investigating the Whole-Genome Sequence of a New Locus of Enterocyte Effacement-Positive Shiga Toxin-Producing Escherichia coli O157:H7 Strain Isolated from River Water.

Zhang Yujie Y Liao Yen-Te YT Salvador Alexandra A Sun Xiaohong X Wu Vivian C H VCH

Microbiology resource announcements 20200319 12

Diverse Shiga toxin-producing <i>Escherichia coli</i> (STEC) strains have been isolated from several environmental samples. Rivers are associated with the distribution of STEC pathogens in the environment. Thus, we report the complete genome sequence of a locus of enterocyte effacement (LEE)-positive STEC O157:H7 strain isolated from the Mississippi River. ...[more]

PMID: 32193236

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Shiga toxin-producing Escherichia coli strains negative for locus of enterocyte effacement.

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Project description:Shiga toxin-producing Escherichia coli (STEC) are important enteropathogens causing severe diseases such as hemorrhagic colitis and hemolytic-uremic syndrome in humans. The majority of STEC strains of serogroups O157, O26, or O111 associated with severe cases of these diseases possess a pathogenicity island termed the locus of enterocyte effacement (LEE). LEE, which is responsible for the formation of attaching-and-effacing lesions on intestinal epithelial cells, is important for the full virulence of STEC. Nonetheless, LEE-negative STEC strains have repeatedly been reported to be associated with severe diseases in humans. In this study, we characterized adhesion to cultured epithelial cells of certain LEE-negative STEC isolated from humans with or without bloody diarrhea. Several LEE-negative STEC belonging to serogroup O91 showed an unusual, chain-like adhesion pattern to HEp-2 cells. Using Tn5-based transposon mutagenesis, we identified the gene essential for the chain-like adhesion phenotype of this O91 STEC strain. Sequence analysis of the Tn5-inserted allele identified a novel chromosomal open reading frame (ORF) encoding a polypeptide with a high degree of similarity to the E. coli immunoglobulin-binding (Eib) proteins EibA, -C, -D, -E, and -F. Therefore, the ORF was designated EibG. Laboratory E. coli strain MC4100 transformed with a multicopy plasmid carrying eibG showed chain-like adhesion to HEp-2 cells, and whole-cell lysates of the strain bound to human-derived immunoglobulin G (IgG) Fc and IgA. These results indicate that EibG acts as an IgG Fc- and IgA-binding protein, as well as an adhesin of LEE-negative STEC.

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Comparison of Shiga toxin-encoding bacteriophages in highly pathogenic strains of Shiga toxin-producing Escherichia coli O157:H7 in the UK.

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