Resistencia a carbapenemes en aislamientos de Pseudomonas aeruginosa: Un ejemplo de interacción entre distintos mecanismos

Translated title of the contribution: Carbapenem resistance in Pseudomonas aeruginosa isolates: An example of interaction between different mechanisms

Gisela Santella, Simona Pollini, Jean Denis Docquier, Marisa Almuzara, Gabriel Gutkind, Gian Maria Rossolini, Marcela Radice

Research output: Contribution to journalArticlepeer-review

Abstract

Objective. To identify the outer membrane protein absent in the resistant isolates and to determine both the causes of its absence in the membrane and the presence of other mechanisms of carbapenem resistance in clinical isolates of Pseudomonas aeruginosa. Methods. Twenty isolates from an outbreak of P. aeruginosa previously characterized as metallo-beta-lactamase IMP-13 producers were studied. All the isolates exhibited equal expression of the IMP-13 enzyme, but only five of them were carbapenemresistant. It was found that the five resistant isolates lacked a outer membrane protein. The oprD and ampC genes were sequenced; the outer membrane proteins were identified using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry; the OprD and AmpC expressions, as well as the Mex efflux system, were assessed by real-time polymerase chain reaction; and finally, the contribution of reduced OprD to carbapenem resistance was determined. Results. The absent outer membrane protein in group R was identified as OprD-TS; however, no variations in its expression were observed. The oprD gene presented mutations in the five resistant isolates. The production of AmpC PDC-5-type enzyme and the MexAB-OprM efflux system was the same in both carbapenem-sensitive and -resistant isolates. The contribution of the combined presence of IMP-13 and reduced OprD to increased resistance was examined. Conclusions. Different mechanisms contribute to carbapenem resistance in IMP- 13-producing isolates. The possibility that these IMP-13-producing isolates could go undetected poses a latent risk when selecting mutants with added resistance mechanisms in order to enhance carbapenem resistance.

Translated title of the contributionCarbapenem resistance in Pseudomonas aeruginosa isolates: An example of interaction between different mechanisms
Original languageSpanish
Pages (from-to)545-548
Number of pages4
JournalRevista Panamericana de Salud Publica/Pan American Journal of Public Health
Volume30
Issue number6
DOIs
Publication statusPublished - Dec 2011

Keywords

  • Argentina
  • Drug resistance, Microbial
  • Pseudomonas aeruginosa

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health

Fingerprint Dive into the research topics of 'Carbapenem resistance in Pseudomonas aeruginosa isolates: An example of interaction between different mechanisms'. Together they form a unique fingerprint.

Cite this