Genomic and functional portrait of multidrug-resistant, hydrogen sulfide (H 2 S)-producing variants of Escherichia coli

Atypical forms exhibit unusual characteristics compared to typical strains. The H S-producing variants of some atypical strains cause a wide range of illnesses in humans and animals. However, there are sparse reports on such strains worldwide. We performed whole-genome sequencing (WGS) and detailed characterization of four H S-producing variants from poultry and human clinical sources in Dhaka, Bangladesh. All four isolates were confirmed as using biochemical tests and genomic analysis, and were multidrug-resistant (MDR). WGS analysis including an additional Chinese strain, revealed diverse STs among the five H S-producing genomes, with clonal complex ST10 being detected in 2 out of 5 genomes. The predominant phylogroup detected was group A ( = 4/5). The ( = 5/5) was the most predominant extended-spectrum beta-lactamase (ESBL) gene, followed by different alleles of ( -55,-65,-123; = 3/5). Multiple plasmid replicons were detected, with IncX being the most common. One strain was classified as enteropathogenic . The genomes of all five isolates harbored five primary and four secondary function genes related to H S production. These findings suggest the potential of these isolates to cause disease and spread antibiotic resistance. Therefore, such atypical forms should be included in differential diagnosis to understand the pathogenicity, antimicrobial resistance and evolution of H S-producing