Genomic Analysis of Multidrug-Resistant from Surface Water in Northeast Georgia, United States: Presence of an ST131 Epidemic Strain Containing on a Phage-Like Plasmid.

Surface water is suspected of playing a role in the development and spread of antimicrobial-resistant (AR) bacteria, including human pathogens. In our previous study, 496 isolates were recovered from water samples collected over a 2-year period from the Upper Oconee watershed, Athens, GA, United States, of which 34 (6.9%) were AR isolates. Of these, six isolates were selected based on their multidrug resistance (MDR) phenotypes, the presence of mobile genetic elements, and their pathogenic potential and were subjected to whole-genome sequence (WGS) analysis to enhance our understanding of environmental MDR isolates. This study is the first report on genomic characterization of MDR from environmental water in the United States through a WGS approach. The sequences of the six MDR isolates were analyzed and the locations of their AR genes were identified. One of the isolates was an ST131 epidemic strain, which also produced an extended-spectrum β-lactamase encoded by the gene, carried on a plasmid that is a member of a very rarely reported family of phage-like plasmids. This is the first time an in-depth sequence analysis has been done on a - containing phage-like plasmid, the presence of which suggests a new emerging mechanism of AR gene transmission.