Genomic analysis of MCR-1 and CTX-M-8 co-producing Escherichia coli ST58 isolated from a polluted mangrove ecosystem in Brazil.

OBJECTIVES: Genomic surveillance studies monitoring the dissemination of multidrug-resistant Enterobacteriaceae in polluted aquatic ecosystems are urgently required. The aim of this study was to report the draft genome sequence of an MCR-1 and CTX-M-8 co-producing Escherichia coli isolated from a polluted mangrove ecosystem in Northeast Brazil.

METHODS: Total genomic DNA was sequenced on an Illumina NextSeq platform and was assembled using CLC Genomics Workbench. The whole-genome sequence was evaluated through bioinformatics tools available from the Center of Genomic Epidemiology as well as additional in silico analysis.

RESULTS: The genome size was calculated at 5089467bp, comprising a total of 5068 protein-coding sequences. The strain was assigned to sequence type 58 (ST58) and revealed the presence of mcr-1, blaCTX-M-8 and other clinically significant genes responsible for conferring resistance to colistin, β-lactams, trimethoprim and quinolones. In addition, genes conferring resistance to silver (silR) and quaternary ammonium compounds (sugE) were identified.

CONCLUSION: These data provide valuable information for comparative genomic analysis regarding the dissemination of MCR-1-producing E. coli at the human-animal-environment interface.