Analysis of Efflux Pump Genes in β-lactam Resistant Clinical Isolates of Pseudomonas aeruginosa from a Tertiary Level Hospital in Ecuador

Article Sidebar

Published: May 30, 2017
DOI: https://doi.org/10.26807/remcb.v38i1.20
Keywords:
Bacterial Resistance, Efflux pumps, -lactams, Pseudomonas aeruginosa, T-qPCR

Main Article Content

Isaac Armendáriz-Castillo
Marcelo Grijalva
María José Vallejo
Patricia Jiménez

Abstract

Pseudomonas aeruginosa is a nosocomial microorganism that causes a wide spectrum of infections and is known as one of the primary multi-resistant microorganisms against β-lactam antibiotics. One of the main resistance mechanisms found in P. aeruginosa is the efflux pumps. This study is aimed at characterizing this mechanism by analyzing the expression of four genes (mexA, mexX, oprJ and oprM) involved in antibiotic efflux pumps in Pseudomonas aeruginosa. Forty clinical isolates (20 resistant, 20 susceptible) were collected from the Bacteriology Laboratory at the Carlos Andrade Marin Hospital, in Quito-Ecuador. Expression levels for the selected genes were assessed by RT-qPCR assays using RpsL as a housekeeping gene for ΔΔCt adjusted relative quantitation analysis. The importance of efflux pumps as a resistance mechanism was corroborated through analysis of efflux pumps genes that showed overexpression in all phenotypically resistant isolates. Furthermore, phenotype/genotype analysis was performed comparing Antibiotic Susceptibility Testing (AST) results with expression profiles. Results for the mexA genotype showed correlation with the TPZ resistance phenotype and the mexX genotype with the IPM, MEM and FEP resistance phenotypes. In conclusion, the expression pattern of the efflux pump genes suggests resistance mechanisms that are due to horizontal transmission or pathogens spreading into the hospital environment.

Downloads

Download data is not yet available.

Article Details

How to Cite
1.
Armendáriz-Castillo I, Grijalva M, Vallejo MJ, Jiménez P. Analysis of Efflux Pump Genes in β-lactam Resistant Clinical Isolates of Pseudomonas aeruginosa from a Tertiary Level Hospital in Ecuador. REMCB [Internet]. 2017May30 [cited 2024Jul.3];38(1):45-4. Available from: https://remcb-puce.edu.ec/remcb/article/view/20
Issue
Vol. 38 No. 1: Mayo 2017
Section
Artículos Científicos

References

BoBolha L, Dusanic D, Narat M , Oven I. 2012. Comparison of methods for relative quantification of gene expression using Real-time PCR. Acta argiculturae Slovenica 100(2):97–106.

Breidenstein E, de la Fuente C, Hancock R. 2011. Pseudomonas aeruginosa: all roads lead to resistance. Cell Press 19(8): 419–426.

Guzmán-Blanco M and Istúriz R. 2010. Antimicrobial Drug Resistance in Latin America and the Caribbean. In: Sosa A, Byarugaba D, Amábile-Cuevas C, Hsueh P, Kariuki S and Okeke, I (eds) Antimicrobial Resistance in Developing Countries: 331–345. Springer. New York.

Khan-Malek, Wang Y. 2011. Statistical Analysis of Quantitative RT-PCR Results. Methods in Molecular Biology 691(1):227–241.

Lister P, Wolder D, Hanson N. 2009. Antibacterial-Resistant Pseudomonas aeruginosa: Clinical impact and complex regulation of chromosomally encoded resistance mechanisms. Clinic Microbiology Review 22(4):582–610.

Meletis G, Begkeri M. 2013. Pseudomonas aeruginosa: Multi-Drug-Resistance Development and Treatment Options. Infection Control. En: Silpi B (ed). Infection Control. In Tech, Croatia. DOI:10.5772/55616.

Morita Y, Tomida J, Kawamura Y. 2012. MexXY multidrug efflux system of Pseudomonas aeruginosa. Frontiers in microbiology 3(1):408–415.

Nolan T, Hands R, Bustin S. 2006. Quantification of mRNA using real-time PCR. Nature protocols 1(3):1559–1582.

Wong M, Medrano J. 2005. Real-Time PCR for mRNA quantitation. BioTechniques 39(1):75–85.

Yuan J, Wang D and Stewart J. 2008. Statistical methods for efficiency adjusted real-time PCR quantification. Biotechnology Journal 3(1):112–123.