Molecular characteristics of <i>eae</i>-positive clinical Shiga toxin-producing <i>Escherichia coli</i> in Sweden
收藏资源简介：
Shiga toxin (Stx)-producing <i>Escherichia coli</i> (STEC) can cause a wide range of symptoms from asymptomatic carriage, mild diarrhea to bloody diarrhea (BD) and hemolytic uremic syndrome (HUS). Intimin, encoded by the <i>eae</i> gene, also plays a critical role in STEC pathogenesis. Herein, we investigated the prevalence and genetic diversity of <i>eae</i> among clinical STEC isolates from patients with diarrhea, BD, HUS as well as from asymptomatic STEC-positive individuals in Sweden with whole-genome sequencing. We found that 173 out of 239 (72.4%) of clinical STEC strains were <i>eae</i> positive. Six <i>eae</i> subtypes (<i>ϵ</i>1, <i>γ</i>1, <i>β</i>3, <i>θ</i>, <i>ζ</i> and <i>ρ</i>) were identified <i>eae</i> and its subtype <i>γ</i>1 were significantly overrepresented in O157:H7 strains isolated from BD and HUS patients. <i>ϵ</i>1 was associated with O121:H19 and O103:H2 strains, and <i>β</i>3 to O26:H11 strains. The combination of <i>eae</i> subtype <i>γ</i>1 and <i>stx</i> subtype (<i>stx</i><sub>2</sub> or <i>stx</i><sub>1</sub>+<i>stx</i><sub>2</sub>) is more likely to cause severe disease, suggesting the possibility of using <i>eae</i> genotypes in risk assessment of STEC infection. In summary, this study demonstrated a high prevalence of <i>eae</i> in clinical STEC strains and considerable genetic diversity of <i>eae</i> in STEC strains in Sweden from 1994 through 2018, and revealed association between <i>eae</i> subtypes and disease severity.
