Draft genome of a ST443 mcr-1- and blaCTX-M-2-carrying Escherichia coli from cattle in Brazil.

OBJECTIVES

Colistin is used in Brazil for the treatment of food-producing animals. The colistin resistance gene mcr-1 has already been reported from chicken and swine in this country. Here we report the draft genome of an Escherichia coli isolate presenting both an extended-spectrum β-lactamase (ESBL) gene and the mcr-1 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 using the NCBI Prokaryotic Genome Annotation Pipeline (PGAP). Further analyses were performed using Center for Genomic Epidemiology databases. Southern blots were performed to characterise plasmid location.

RESULTS

The 5024393-bp genome displayed several resistance genes, including the mcr-1 and blaCTX-M-2 genes. These two genes were located on different plasmids (mcr-1 on an IncX4 plasmid and blaCTX-M-2 on an IncF plasmid).

CONCLUSION

The genome sequence reported here can be compared with previously published genomes for mcr-1-producing isolates. This will ultimately help to understand the routes of dissemination of the resistance genes.