Université de Fribourg

KPC-50 confers resistance to ceftazidime-avibactam associated with reduced carbapenemase activity

Poirel, Laurent ; Vuillemin, Xavier ; Juhas, Mario ; Masseron, Amandine ; Bechtel-Grosch, Ursina ; Tiziani, Simon ; Mancini, Stefano ; Nordmann, Patrice

In: Antimicrobial Agents and Chemotherapy, 2020, vol. 64, no. 8, p. -

KPC-50 is a KPC-3 variant identified from a Klebsiella pneumoniae clinical isolate recovered in Switzerland in 2019. Compared to KPC-3, KPC-50 shows (i) a three- amino-acid insertion (Glu-Ala-Val) between amino acids 276 and 277, (ii) an increased affinity to ceftazidime, (iii) a decreased sensitivity to avibactam, explaining the ceftazidime-avibactam resistance, and (iv) an association with a...

Université de Fribourg

Identification of fosa8, a plasmid-encoded fosfomycin resistance determinant from Escherichia coli, and its origin in Leclercia adecarboxylata

Poirel, Laurent ; Vuillemin, Xavier ; Kieffer, Nicolas ; Mueller, Linda ; Descombes, Marie-Christine ; Nordmann, Patrice

In: Antimicrobial Agents and Chemotherapy, 2019, vol. 63, no. 11, p. -

A plasmid-located fosfomycin resistance gene, fosA8, was identified from a CTX-M- 15-producing Escherichia coli isolate recovered from urine. Identification of this gene was obtained by whole-genome sequencing. It encoded FosA8, which shares 79% and 78% amino acid identity with the most closely related FosA2 and FosA1 enzymes, respectively. The fosA8 gene was located on a transferable 50-kb...

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:...