International Microbiology, Vol 14, No 1 (2011)

A mechanism of carbapenem resistance due to a new insertion element (ISPa133) in Pseudomonas aeruginosa

Lidia Ruiz-Martínez, Lidia López-Jiménez, Valeria d’Ostuni,, Ester Fusté, Teresa Vinuesa, Miguel Viñas

Abstract


This study explored the evolutionary mechanism by which the clinical isolate PA110514 yields the imipenemresistant
derivative PA116136. Both isolates were examined by PFGE and SDS-PAGE, which led to the identification of a new insertion sequence, ISPa133. This element was shown to have distinct chromosomal locations in each of the original isolates
that appeared to explain the differences in imipenem susceptibilty. In strain PA110514, ISPa133 is located 56 nucleotides upstream of the translational start codon, which has no effect on expression of the porin OprD. However, in strain PA116136 ISPa133 it is located in front of nucleotide 696 and, by interrupting the coding region, causes a loss of OprD expression, thus conferring imipenem resistance. In vitro experiments mimicking the natural conditions of selective pressure yielded imipenem- resistant strains in which ISPa133 similarly interrupted oprD. Amechanism is proposed whereby ISPa133 acts as a mobile switch, with its position in oprD depending on the degree of selective pressure exerted by imipenem. [Int Microbiol 2011; 14(1):51-58]

Full Text: PDF

Sello de Calidad FECYT

 

 

5-year Impact Factor of International Microbiology is 2,10.

The journal is covered in several leading abstracting and indexing databases, including the following ones: AFSA Marine Biotechnology Abstracts; Biological Abstracts; Biotechnology Research Abstracts; BIOSIS Previews; CAB Abstracts; Chemical Abstracts; Current Contents–Agriculture, Biology & Environmental Sciences; EBSCO; Embase; Food Science and Technology Abstracts; Google Scholar; IEDCYT; IBECS; Latíndex; MedBioWorld; PubMed; SciELO-Spain; Science Citation Index Expanded; Scopus

 

Creative Commons License

This work, including photographs and other illustrations, unless the contrary is indicated, is subject to an Attributions–Non-Commercial–ShareAlike 3.0 Creative Commons License, the full text of which can be consulted at http://creativecommons.org/licenses/by-nc-sa/3.0/. You are free to share, copy, distribute and transmit the work provided that the author is credited and reuse of the material is restricted to non-commercial purposes only and that if you alter, transform, or build upon this work, you may distribute the resulting work only under the same or similar license to this one. 

 

Copyright ® 2013 by Spanish Society for Microbiology (SEM)