Multidrug-resistant Shiga toxin-producing Escherichia coli and hybrid pathogenic strains of bovine origin

AbstractAntimicrobial-resistantEscherichia coli strains have been circulating in various sectors and can be cross-transferred between them. Among pathogenicE. coli strains, Shiga toxin-producingE. coli (STEC) and hybrid pathogenicE. coli (HyPEC) emerged as responsible for outbreaks worldwide. As bovine are reservoir of STEC strains, these pathogens primarily spread to food products, exposing humans to risk. Therefore, this study aimed to characterize antimicrobial-resistant and potentially pathogenicE. coli strains from fecal samples of dairy cattle. In this regard, mostE. coli strains (phylogenetic groups A, B1, B2, and E) were resistant to β-lactams and non-β-lactams and were classified as multidrug-resistant (MDR). Antimicrobial resistance genes (ARGs) related to multidrug resistance profiles were detected. Furthermore, mutations in fluoroquinolone and colistin resistance determinants were also identified, highlighting the deleteri ous mutation His152Gln in PmrB that may have contributed to the high level (>  64 mg/L) of colistin resistance. Virulence genes of diarrheagenic and extraintestinal pathogenicE. coli (ExPEC) pathotypes were shared among strains and even within the same strain, evidencing the presence of HyPEC (i.e., ExPEC/STEC), which were assigned as unusual B2-ST126-H3 and B1-ST3695-H31. These findings provide phenotypic and molecular data of MDR, ARGs-producing, and potentially pathogenicE. coli strains in dairy cattle, contributing to the monitoring ...
Source: Veterinary Research Communications - Category: Veterinary Research Source Type: research