Université de Fribourg

Acquisition of extended-spectrum β-lactamase GES-6 leading to resistance to ceftolozane-tazobactam combination in Pseudomonas aeruginosa

Poirel, Laurent ; Ortiz De La Rosa, José-Manuel ; Kieffer, Nicolas ; Dubois, Véronique ; Jayol, Aurélie ; Nordmann, Patrice

In: Antimicrobial Agents and Chemotherapy, 2019, vol. 63, no. 1, p. e01809-18

A clinical Pseudomonas aeruginosa isolate resistant to all β-lactams, including ceftolozane-tazobactam and carbapenems, was recovered. It belonged to sequence type 235 and produced the extended-spectrum β-lactamase (ESBL) GES-6 differing from GES-1 by two amino acid substitutions (E104K and G170S). GES-6 possessed an increased hydrolytic activity toward carbapenems and to ceftolozane and a ...

Université de Fribourg

Antimicrobial activity of octenidine against multidrug-resistant Gram-negative pathogens

Alvarez-Marin, R. ; Aires-de-Sousa, Marta ; Nordmann, Patrice ; Kieffer, Nicolas ; Poirel, Laurent

In: European Journal of Clinical Microbiology & Infectious Diseases, 2017, p. 1–5

Multidrug-resistant (MR) Gram-negative (GN) pathogens pose a major and growing threat for healthcare systems, as therapy of infections is often limited due to the lack of available systemic antibiotics. Well-tolerated antiseptics, such as octenidine dihydrochloride (OCT), may be a very useful tool in infection control to reduce the dissemination of MRGN. This study aimed to investigate the...

Université de Fribourg

Antimicrobial Resistance in Escherichia coli

Poirel, Laurent ; Madec, Jean-Yves ; Lupo, Agnese ; Schink, Anne-Kathrin ; Kieffer, Nicolas ; Nordmann, Patrice ; Schwarz, Stefan

In: Microbiology Spectrum, 2018, vol. 6, no. 4, p. -

Multidrug resistance in Escherichia coli has become a worrying issue that is increasingly observed in human but also in veterinary medicine worldwide. E. coli is intrinsically susceptible to almost all clinically relevant antimicrobial agents, but this bacterial species has a great capacity to accumulate resistance genes, mostly through horizontal gene transfer. The most problematic...

Université de Fribourg

Characterization of PAN-1, a carbapenem-hydrolyzing class b β-lactamase from the environmental gram-negative Pseudobacteriovorax antillogorgiicola

Kieffer, Nicolas ; Poirel, Laurent ; Fournier, Claudine ; Haltli, Brad ; Kerr, Russel ; Nordmann, Patrice

In: Frontiers in Microbiology, 2019, vol. 10, p. -

The gene encoding the metallo-β-lactamase (MβL) PAN-1 was identified in the genome of the environmental Gram-negative species Pseudobacteriovorax antillogorgiicola. PAN-1 shares 57% amino-acid identity with the acquired MβL SPM- 1, its closest relative. Kinetic parameters performed on purified PAN-1 showed it displayed a hydrolytic activity toward most β-lactams including carbapenems but ...

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:...