Characterization of a new genetic environment associated with GES-6 carbapenemase from a Pseudomonas aeruginosa isolate belonging to the high-risk clone ST235

Abstract

Pseudomonas aeruginosa is an opportunistic pathogen commonly associated with nosocomial infections.1 The spread of P. aeruginosa strains resistant to carbapenems constitutes an emerging threat worldwide.1 The GES family of enzymes has been identified in several Gram-negative bacteria, such as P. aeruginosa, Klebsiella pneumoniae and Escherichia coli, being responsible for an extended resistance spectrum to several -lactams.2,3 To date, according to the Lahey Clinic web site (http://www.lahey.org/Studies/), 24 variants of GES have been identified with some presenting carbapenemase activity, which is a matter of great concern. Few GES variants have been identified in Portugal, all of them found in Enterobacteriaceae.3 In Portugal, carbapenemases associated with P. aeruginosa include VIM-2 (the most frequent) and also IMP-5.4 Here, we report the first known worldwide description of the blaGES-6 gene in P. aeruginosa strains associated with a new genetic environment and also the first description of GES-producing P. aeruginosa in Portugal.