Open AccessDiversity of blaCTX-M-1-carrying plasmids recovered from Escherichia coli isolated from Canadian domestic animals
Author(s) -
Ashley C. Cormier,
Gabhan Chalmers,
Roxana Zamudio,
Michael R. Mulvey,
Alison E. Mather,
Patrick Boerlin
Publication year - 2022
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0264439
Subject(s) - plasmid , biology , escherichia coli , multilocus sequence typing , beef cattle , nanopore sequencing , genetic diversity , genome , microbiology and biotechnology , veterinary medicine , genetics , gene , genotype , population , medicine , demography , sociology
Conserved IncI1 and IncHI1 plasmids carrying bla CTX-M-1 have been found circulating in chickens and horses from continental Europe, respectively. In Canada, bla CTX-M-1 is overwhelmingly the most common bla CTX-M variant found in Escherichia coli from chicken and horses and can be recovered at lower frequencies in swine, cattle, and dogs. Whole-genome sequencing has identified a large genetic diversity of isolates carrying this variant, warranting further investigations into the plasmids carrying this gene. Therefore, the objective of this study was to describe the genetic profiles of bla CTX-M-1 plasmids circulating in E . coli from Canadian domestic animals and compare them to those recovered in animals in Europe. Fifty-one bla CTX-M-1 positive E . coli isolates from chicken (n = 14), horses (racetrack horses n = 11; community horses n = 3), swine (n = 7), turkey (n = 6), dogs (n = 5), beef cattle (n = 3), and dairy cattle (n = 2) were selected for plasmid characterization. Sequences were obtained through both Illumina and Oxford Nanopore technologies. Genomes were assembled using either Unicycler hybrid assembly or Flye with polishing performed using Pilon. bla CTX-M-1 was found residing on a plasmid in 45 isolates and chromosomally located in six isolates. A conserved IncI1/ST3 plasmid was identified among chicken (n = 12), turkey (n = 4), swine (n = 6), dog (n = 2), and beef cattle (n = 2) isolates. When compared against publicly available data, these plasmids showed a high degree of similarity to those identified in isolates from poultry and swine in Europe. These results suggest that an epidemic IncI1/ST3 plasmid similar to the one found in Europe is contributing to the spread of bla CTX-M-1 in Canada. A conserved IncHI1/FIA(HI1)/ST2 plasmid was also recovered from nearly all racetrack horse isolates (n = 10). Although IncHI1/ST2 plasmids have been reported among European horse isolates, IncHI1/ST9 plasmids appear to be more widespread. Further studies are necessary to understand the factors contributing to these plasmids’ success in their respective populations.