The mobile colistin resistance gene mcr-1 has attracted global attention, as it heralds the breach of polymyxins, one of the last-resort antibiotics for the treatment of severe clinical infections caused by multidrug-resistant Gram-negative bacteria. To date, six slightly different variants of mcr-1, and a second mobile colistin resistance gene, mcr-2, have been reported or annotated in the GenBank database. Here, we characterized a third mobile colistin resistance gene, mcr-3. The gene coexisted with 18 additional resistance determinants in the 261-kb IncHI2-type plasmid pWJ1 from porcine Escherichia coli. mcr-3 showed 45.0% and 47.0% nucleotide sequence identity to mcr-1 and mcr-2, respectively, while the deduced amino acid sequence of MCR-3 showed 99.8 to 100% and 75.6 to 94.8% identity to phosphoethanolamine transferases found in other Enterobacteriaceae species and in 10 Aeromonas species, respectively. pWJ1 was mobilized to an E. coli recipient by conjugation and contained a plasmid backbone similar to those of other mcr-1-carrying plasmids, such as pHNSHP45-2 from the original mcr-1-harboring E. coli strain.
Original Source [2]
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/novel-plasmid-mediated-colistin-resistance-gene-mcr-3-escherichia-coli
[2] http://mbio.asm.org/content/8/3/e00543-17.full
[3] http://admin.indiaenvironmentportal.org.in/category/author/wenjuan-yina
[4] http://admin.indiaenvironmentportal.org.in/category/author/hui-lia
[5] http://admin.indiaenvironmentportal.org.in/category/author/yingbo-shen-et-al
[6] http://admin.indiaenvironmentportal.org.in/category/journal/mbio
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/micro-organisms
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/antibiotic
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/infectious-diseases