Acquisition of class C β-lactamase PAC-1 by ST664 strains of Pseudomonas aeruginosa

Antimicrob Agents Chemother. 2019 Sep 9;63(12):e01375-19. doi: 10.1128/AAC.01375-19. Epub 2019 Sep 16.

Abstract

Four ST664 (serotype O:5) strains of Pseudomonas aeruginosa highly resistant to antibiotics including ceftolozane/tazobactam and ceftazidime/avibactam but susceptible to colistin, were found to harbor the rare class C β-lactamase PAC-1 encoding gene on a chromosomally-located Tn1721-like transposon. Gene bla PAC-1 was associated with the 16S rRNA methylase determinant rmtF2, that confers pan-aminoglycoside resistance. These genotypically-related strains were isolated in repatriated patients from Mauricius and Afghanistan and close to a lineage reported in Nepal, Pakistan and India.