Abstract:
Escherichia coli, both commensal and pathogenic,
can colonize plants and persist in various environments. It indicates
fecal contamination in water and food and serves as a marker of
antimicrobial resistance. In this context, 61 extended-spectrum βlactamase (ESBL)-producing E. coli from irrigation water and fresh
produce from previous studies were characterized using whole
genome sequencing (Illumina MiSeq). The Center for Genomic
Epidemiology and Galaxy platforms were used to determine
antimicrobial resistance genes, virulence genes, plasmid typing,
mobile genetic elements, multilocus sequence typing (MLST), and
pathogenicity prediction. In total, 19 known MLST groups were
detected among the 61 isolates. Phylogroup B1 (ST58) and
Phylogroup E (ST9583) were the most common sequence types.
The six ST10 (serotype O101:H9) isolates carried the most resistance genes, spanning eight antibiotic classes. Overall, 95.1% of the
isolates carried resistance genes from three or more classes. The blaCTX‑M‑1, blaCTX‑M‑14, and blaCTX‑M‑15 ESBL genes were associated
with mobile genetic elements, and all of the E. coli isolates showed a >90% predicted probability of being a human pathogen. This
study provided novel genomic information on environmental multidrug-resistant ESBL-producing E. coli from fresh produce and
irrigation water, highlighting the environment as a reservoir for multidrug-resistant strains and emphasizing the need for ongoing
pathogen surveillance within a One Health context.
