Identification and pathogenomic analysis of an Escherichia coli strain producing a novel Shiga toxin 2 subtype.

ABSTRACT: Shiga toxin (Stx) is the key virulent factor in Shiga toxin-producing Escherichia coli (STEC). To date, three Stx1 subtypes and seven Stx2 subtypes have been described in E. coli, which differed in receptor preference and toxin potency. Here, we identified a novel Stx2 subtype designated Stx2h in E. coli strains isolated from wild marmots in the Qinghai-Tibetan plateau, China. Stx2h shares 91.9% nucleic acid sequence identity and 92.9% amino acid identity to the nearest Stx2 subtype. The expression of Stx2h in type strain STEC299 was inducible by mitomycin C, and culture supernatant from STEC299 was cytotoxic to Vero cells. The Stx2h converting prophage was unique in terms of insertion site and genetic composition. Whole genome-based phylo- and patho-genomic analysis revealed STEC299 was c

SUBMITTER: Bai X 

PROVIDER: S-EPMC5928088 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature