Pandemic Escherichia coli ST648 isolate harbouring fosA3 and blaCTX-M-8 on an IncI1/ST113 plasmid: A new successful combination for the spread of fosfomycin resistance?

OBJECTIVES

The emergence of Enterobacteriaceae isolates resistant to the last-resort antibiotic fosfomycin outside of Asia is a public-health issue. Here we report the draft genome of an Escherichia coli isolate presenting both an extended-spectrum β-lactamase (ESBL) and the fosA3 gene in a healthy cow in Brazil.

METHODS

Whole genomic DNA from E. coli E12 was extracted and 2×150-bp paired-end reads were generated using Illumina sequencing technology. De novo genome assembly was performed using SPAdes v.3.11 and the draft genome was annotated by the NCBI Prokaryotic Genome Annotation Pipeline. Further analyses were performed using the Center for Genomic Epidemiology databases.

RESULTS

The 5045934-bp genome displayed several resistance genes, including the fosA3 and blaCTX-M-8 genes. Southern blot experiments showed that they were co-located on an IncI1/ST113 plasmid.

CONCLUSION

Presence of the fosA3 gene on the same common plasmid as blaCTX-M-8 will have to be monitored. This draft genome provides data that will help in tracing the dissemination of this gene and the evolution of its plasmidic support.