Inactivation of the oprD porin gene by a novel insertion sequence ISPa195 associated with large deletion in a carbapenem-resistant Pseudomonas aeruginosa clinical isolate. (June 2019)

• Record Type: Journal Article
• Authors: Bocharova, Yuliya; Savinova, Tatiana; Shagin, Dmitriy A.; Shelenkov, Andrey A.; Mayanskiy, Nikolay A.; Chebotar, Igor V.
• Is Part Of: Journal of global antimicrobial resistance. Volume 17(2019)
• Page Start: 309
• Page End: 311
• Publication Date: 2019-06
• Subjects: Pseudomonas aeruginosa -- Carbapenem resistance -- Insertion sequence -- ISPa195; Drug resistance -- Periodicals; Drug resistance -- Periodicals; Drug resistance; Periodicals; 616.9041
• DOI: 10.1016/j.jgar.2019.01.016
• Languages: English
• ISSNs: 2213-7165

Abstract

Highlights: New insertion sequence ISPa195 was found in oprD of carbapenem resistant Pseudomonas aeruginosa . An IS-associated deletion was detected in oprD of ISPa195 -positive isolate. There were no direct repeats at flanking regions of ISpa195 . The oprD gene alteration was combined with carbapenem-efflux in ISPa195 -positive P. aeruginosa . Abstract: Objectives: Alteration of the porin-encoding gene oprD by insertion sequences (ISs) is one mechanism conferring carbapenem resistance in Pseudomonas aeruginosa. Here we describe a carbapenem-resistant clinical P. aeruginosa isolate 36-989 harbouring a novel IS (IS Pa195 ) in oprD . Methods: Minimum inhibitory concentrations (MICs) of antimicrobial agents were determined by the broth microdilution method. Carbapenemase activity was assessed using a MALDI-TOF/MS-based assay of meropenem hydrolysis. Efflux-dependent carbapenem resistance was evaluated using an assay with carbonyl cyanide 3-chlorophenylhydrazone (CCCP). The oprD gene and IS sequence were analysed by the Sanger method. Whole-genome sequencing was performed on an Illumina HiSeq 2500 platform. Results: Antimicrobial susceptibility testing demonstrated that P. aeruginosa 36-989 was resistant to imipenem (MIC = 32 mg/L) and meropenem (MIC = 16 mg/L). No carbapenemase activity was detected, however an efflux-mediated component of carbapenem resistance was revealed. A new IS element (IS Pa195 ) was found in the oprD gene of P. aeruginosa 36-989. IS Pa195 was 1190 bp in length, belonging to the IS 3 family, and contained two open reading frames that overlapped through a ribosomal slippage to translate the full-size transposase enzyme. There was an IS-associated 284-bp deletion in the oprD gene; no direct repeats at flanking regions of the IS were detected. Conclusion: The absence of direct repeats at flanking regions in combination with the IS-associated deletion distinguished IS Pa195 from other ISs previously detected in oprD . Carbapenem resistance in P. aeruginosa 36-989 was conferred by a combination of oprD alteration and carbapenem efflux.