Analysis of bla _CTX-M -Carrying Plasmids from Escherichia coli Isolates Collected in the BfT-GermVet Study

Abstract

In this study, 417 Escherichia coli isolates from defined disease conditions of companion and farm animals collected in the BfT-GermVet study were investigated for the presence of extended-spectrum ␤-lactamase (ESBL) genes. Three ESBL-producing E. coli isolates were identified among the 100 ampicillin-resistant isolates. The E. coli isolates 168 and 246, of canine and porcine origins, respectively, harbored bla CTX-M-1 , and the canine isolate 913 harbored bla CTX-M-15 , as confirmed by PCR and sequence analysis. The isolates 168 and 246 belonged to the novel multilocus sequence typing (MLST) types ST1576 and ST1153, respectively, while isolate 913 had the MLST type ST410. The ESBL genes were located on structurally related IncN plasmids in isolates 168 and 246 and on an IncF plasmid in isolate 913. The bla CTX-M-1 upstream regions of plasmids pCTX168 and pCTX246 were similar, whereas the downstream regions showed structural differences. The genetic environment of the bla CTX-M-15 gene on plasmid pCTX913 differed distinctly from that of both bla CTX-M-1 genes. Detailed sequence analysis showed that the integration of insertion sequences, as well as interplasmid recombination events, accounted for the structural variability in the bla CTX-M gene regions.

Antibiotic Resistance: How Much Do We Know and Where Do We Go from Here?

“…The same group also characterized MDR E. coli isolates from hospitalized animals, further illustrating that animal-associated commensal E. coli strains possess a wide array of transferable genetic determinants (11). A similar conclusion was also derived by Schink et al (21) through the study of bla CTX-M-1 genes from E. coli. It is worth noting, however, that the evolution of resistant bacteria varies depending on the antibiotic and in many cases is affected by host and environmental factors as well as the local microbial population.…”

“…Extensive investigation of these organisms enabled the establishment of an in-depth understanding of AR mechanisms and prevalence, and many of the discoveries have broad implications. For instance, Schink et al (21) examined extended-spectrum ␤-lactamase (ESBL) genes in E. coli isolates from companion and farm animals with defined disease conditions. They concluded that the presence of identical bla CTX-M-15 genes in diverse plasmid backgrounds in different members of the Enterobacteriaceae from human and animal sources in different countries highlighted the incredible flexibility of resistance plasmids to undergo structural changes in response to evolutionary needs.…”

Characterization of ESBL-producing Escherichia coli recovered from companion dogs in Tai'an, China

“…coli of ST410 carrying the bla CTX-M-15 gene has been detected in dog urinary samples and human samples in China and other countries [16,[25][26][27]. E. coli of ST648 carrying bla CTX-M-15 gene has been frequently found in clinical ESBL-producing E. coli isolates from humans and animals worldwide [15,16,24,28], and therefore the ESBL-producing E. coli of ST648 is regarded as the potential extended-host spectrum genotype.…”

Prevalence of Extended-Spectrum β-Lactamase-Producing Escherichia coli on Bavarian Dairy and Beef Cattle Farms

“…They were not only detected in humans (1,2), but also in a broad range of animal species ranging from companion animals (3)(4)(5) to food animals (6-10), and they could also be found in food (11,12). Extended-spectrum ␤-lactamases are plasmid-encoded enzymes that inactivate a large number of ␤-lactam antibiotics, including extended-spectrum and very-broad-spectrum cephalosporins and monobactams.…”