Emergent Escherichia coli of the highly virulent B2-ST1193 clone producing KPC-2 carbapenemase in ready-to-eat vegetable.

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Critical priority carbapenem-resistant pathogens constitute a worldwide public health problem. Escherichia coli ST1193 is an emerging high-risk clone that demonstrates prolonged gut persistence, and association with community-onset urinary and bloodstream infections. The purpose of this study is to report microbiological and genomic data on the emergence of KPC-2-producing E. coli ST1193 in ready-to-eat (RTE) vegetable. RTE vegetables were purchased from markets in southeastern Brazil. Epiphytic and endophytic Gram-negative bacteria displaying resistance to broad-spectrum beta-lactams were identified by MALDI-TOF. WGS was conducted using the Illumina NextSeq platform. Antimicrobial susceptibility, conjugation, and acid tolerance assays were performed. Virulence behavior was evaluated using the Galleria mellonella infection model. Epiphytic KPC-2-producing E. coli belonging to pandemic ST1193 was identified in RTE arugula. Genomic analysis predicted clinically relevant genes conferring resistance to β-lactams, fluoroquinolones, hazardous heavy metals, pesticides, disinfectants, and chlorine sanitizer. The blaKPC-2 gene was carried by a conjugative IncF plasmid. Resistance of E. coli KPC-2/ST1193 at pH 2.0 was confirmed, being associated with gadWX and ibaG pH tolerance genes, supporting survival to stomach acid prior to reaching small intestine, and potential for a dietary mode of host colonization. Virulent behavior was supported by wide virulome of the highly virulent phylogroup B2, whereas cgSNP-based phylogenomics revealed clonal relationship with healthcare-associated lineages circulating in the United States, China, Mexico, France and Brazil. We report the occurrence of KPC-2-producing E. coli of the highly virulent B2-ST1193 clone in RTE vegetable, highlighting a possible route of dissemination of WHO priority pathogens to humans.