Comparative genomics of clinical hybrid Escherichia coli strains in Norway.
Misti D Finton, Roger Meisal, Davide Porcellato, Lin T Brandal, Bj��rn-Arne Lindstedt
Author Information
Misti D Finton: Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, ��s, Norway.
Roger Meisal: Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, ��s, Norway.
Davide Porcellato: Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, ��s, Norway.
Lin T Brandal: Department of Zoonotic, Food, and Waterborne Infections, Norwegian Institute of Public Health, Oslo, Norway.
Bj��rn-Arne Lindstedt: Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, ��s, Norway. Electronic address: bjorn-arne.lindstedt@nmbu.no.
The global rise of hybrid Escherichia coli (E. coli) is a major public health concern, as enhanced virulence from multiple pathotypes complicates the traditional E. coli classification system and challenges clinical diagnostics. Hybrid strains are particularly concerning as they can infect both intestinal and extraintestinal sites, complicating treatment and increasing the risk of severe disease. This study analyzed virulence-associated genes (VAGs) in 13 E. coli isolates from fecal samples of patients with symptoms of gastrointestinal (GI) infection in Norwegian hospitals and clinics. Whole genome sequencing (WGS) was conducted using Oxford Nanopore's MinION and Illumina's MiSeq platforms. Eleven strains harbored molecular diagnostic markers of atypical enteropathogenic E. coli (aEPEC), enteroinvasive E. coli (EIEC), Shiga toxin-producing E. coli (STEC), enterotoxigenic E. coli (ETEC), or typical enteropathogenic E. coli (tEPEC). Two of those isolates were identified as triple intestinal hybrids with molecular diagnostic markers for aEPEC, EIEC, and STEC. Notably, two isolates lacked any IPEC-specific molecular diagnostic markers, yet were suspected of causing the patient's GI infection. Furthermore, genes associated with extraintestinal pathogenic E. coli (ExPEC)-including adhesins, toxins, protectins, siderophores, iron acquisition systems, and invasins-were identified in all the isolates. Thus, most of the isolates were classified as hybrid aEPEC/ExPEC, STEC/ExPEC, tEPEC/ExPEC, or aEPEC/EIEC/STEC/ExPEC. These findings emphasize the genomic plasticity of E. coli and highlight the need to revise the classification system for enteric pathogens.
