Global Phylogenetic Analysis Of Escherichia coli And Plasmids Carrying The mcr-1 Gene Indicates Bacterial Diversity But Plasmid Restriction

Matamoros, S.; van Hattem, J. M.; Arcilla, M. S.; Willemse, N.; Melles, D.; Penders, J.; Nguyen Vinh, T.; Ngo Thi, H.; COMBAT consortium,; de Jong, M. D.; Schultsz, C.

doi:10.1101/136804

bioRxiv · 10.1101/136804

Global Phylogenetic Analysis Of Escherichia coli And Plasmids Carrying The mcr-1 Gene Indicates Bacterial Diversity But Plasmid Restriction

Matamoros, S.·van Hattem, J. M.·Arcilla, M. S.·Willemse, N.·Melles, D.·Penders, J.·Nguyen Vinh, T.·Ngo Thi, H.·COMBAT consortium,·de Jong, M. D.·Schultsz, C.

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Abstract

To understand the dynamics behind the worldwide spread of the mcr-1 gene, we determined the population structure of Escherichia coli and of mobile genetic elements (MGEs) carrying the mcr-1 gene. After a systematic review of the literature we included 65 E. coli whole genome sequences (WGS), adding 6 recently sequenced travel related isolates, and 312 MLST profiles. We included 219 MGEs described in 7 Enterobacteriaceae species isolated from human, animal and environmental samples. Despite a high overall diversity, 2 lineages were observed in the E. coli population that may function as reservoirs of the mcr-1 gene, the largest of which was linked to ST10, a sequence type known for its ubiquity in human faecal samples and in food samples. No genotypic clustering by geographical origin or isolation source was observed. Amongst a total of 13 plasmid incompatibility types, the Incl2, lncX4 and IncHI2 plasmids accounted for more than 90% of MGEs carrying the mcr-1 gene. We observed significant geographical clustering with regional spread of lncHI2 plasmids in Europe and Incl2 in Asia. These findings point towards promiscuous spread of the mcr-1 gene by efficient horizontal gene transfer dominated by a limited number of plasmid incompatibility types.

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Matamoros, S., van Hattem, J. M., Arcilla, M. S., Willemse, N., Melles, D., Penders, J., Nguyen Vinh, T., Ngo Thi, H., COMBAT consortium,, de Jong, M. D., Schultsz, C.. 2017-05-11. Global Phylogenetic Analysis Of Escherichia coli And Plasmids Carrying The mcr-1 Gene Indicates Bacterial Diversity But Plasmid Restriction. https://doi.org/10.1101/136804

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