Université de Fribourg

Colistin resistance in Parisian inpatient faecal Escherichia coli as the result of two distinct evolutionary pathways

Bourrel, Anne Sophie ; Poirel, Laurent ; Royer, Guilhem ; Darty, Mélanie ; Vuillemin, Xavier ; Kieffer, Nicolas ; Clermont, Olivier ; Denamur, Erick ; Nordmann, Patrice ; Decousser, Jean-Winoc ; The IAME Resistance Group

In: Journal of Antimicrobial Chemotherapy, 2019, vol. 74, no. 6, p. 1521–1530

Beyond plasmid-encoded resistance (mcr genes) prevalence in strain collections, large epidemiological studies to estimate the human burden of colistin-resistant Escherichia coli gut carriage are lacking.Objectives: To evaluate the prevalence of colistin-resistant E. coli carriage in inpatients and decipher the molecular support of resistance and the genetic background of the strains.Methods:...

Université de Fribourg

mcr-9, An inducible gene encoding an acquired phosphoethanolamine transferase in Escherichia coli, and its origin

Kieffer, Nicolas ; Royer, b Guilhem ; Decousser, Jean-Winoc ; Bourrel, Anne-Sophie ; Palmieri, Mattia ; Ortiz De La Rosa, Jose-Manuel ; Jacquier, Hervé ; Denamur, Erick ; Nordmann, Patrice ; Poirel, Laurent

In: Antimicrobial Agents and Chemotherapy, 2019, vol. 63, no. 9, p. -

The plasmid-located mcr-9 gene, encoding a putative phosphoethanolamine transferase, was identified in a colistin-resistant human fecal Escherichia coli strain belonging to a very rare phylogroup, the D-ST69-O15:H6 clone. This MCR-9 protein shares 33% to 65% identity with the other plasmid-encoded MCR-type enzymes identified (MCR-1 to -8) that have been found as sources of acquired resistance...