mcr-9, an Inducible Gene Encoding an Acquired Phosphoethanolamine Transferase in Escherichia coli, and Its Origin.

Détails

ID Serval
serval:BIB_A285C60BFA62
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
mcr-9, an Inducible Gene Encoding an Acquired Phosphoethanolamine Transferase in Escherichia coli, and Its Origin.
Périodique
Antimicrobial agents and chemotherapy
Auteur⸱e⸱s
Kieffer N., Royer G., Decousser J.W., Bourrel A.S., Palmieri M., Ortiz De La Rosa J.M., Jacquier H., Denamur E., Nordmann P., Poirel L.
ISSN
1098-6596 (Electronic)
ISSN-L
0066-4804
Statut éditorial
Publié
Date de publication
09/2019
Peer-reviewed
Oui
Volume
63
Numéro
9
Langue
anglais
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: epublish
Résumé
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 to polymyxins in Enterobacteriaceae Analysis of the lipopolysaccharide of the MCR-9-producing isolate revealed a function similar to that of MCR-1 by adding a phosphoethanolamine group to lipid A and subsequently modifying the structure of the lipopolysaccharide. However, a minor impact on susceptibility to polymyxins was noticed once the mcr-9 gene was cloned and produced in an E. coli K-12-derived strain. Nevertheless, we showed here that subinhibitory concentrations of colistin induced the expression of the mcr-9 gene, leading to increased MIC levels. This inducible expression was mediated by a two-component regulatory system encoded by the qseC and qseB genes located downstream of mcr-9 Genetic analysis showed that the mcr-9 gene was carried by an IncHI2 plasmid. In silico analysis revealed that the plasmid-encoded MCR-9 shared significant amino acid identity (ca. 80%) with the chromosomally encoded MCR-like proteins from Buttiauxella spp. In particular, Buttiauxella gaviniae was found to harbor a gene encoding MCR-BG, sharing 84% identity with MCR-9. That gene was neither expressed nor inducible in its original host, which was fully susceptible to polymyxins. This work showed that mcr genes may circulate silently and remain undetected unless induced by colistin.
Mots-clé
Anti-Bacterial Agents/pharmacology, Colistin/pharmacology, Drug Resistance, Bacterial/genetics, Escherichia coli/drug effects, Escherichia coli/enzymology, Escherichia coli/genetics, Escherichia coli Proteins/genetics, Escherichia coli Proteins/metabolism, Ethanolaminephosphotransferase/genetics, Ethanolaminephosphotransferase/metabolism, Microbial Sensitivity Tests, Plasmids/genetics, Polymyxins/pharmacology, Escherichia coli, MCR, MCR-9, colistin, plasmid, polymyxin
Pubmed
Web of science
Open Access
Oui
Création de la notice
24/06/2019 16:43
Dernière modification de la notice
09/07/2020 5:22
Données d'usage