TY - JOUR
T1 - Evaluation of fluoroquinolone resistance mechanisms in Pseudomonas aeruginosa multidrug resistance clinical isolates
AU - Pasca, Maria Rosalia
AU - Dalla Valle, Claudia
AU - De Jesus Lopes Ribeiro, Ana Luisa
AU - Buroni, Silvia
AU - Papaleo, Maria Cristiana
AU - Bazzini, Silvia
AU - Udine, Claudia
AU - Incandela, Maria Loreto
AU - Daffara, Silvio
AU - Fani, Renato
AU - Riccardi, Giovanna
AU - Marone, Piero
PY - 2012/2/1
Y1 - 2012/2/1
N2 - Efflux transporters have a considerable role in the multidrug resistance (MDR) of Pseudomonas aeruginosa, an important nosocomial pathogen. In this study, 45 P. aeruginosa clinical strains, with an MDR phenotype, have been isolated in a hospital of Northern Italy and characterized to identify the mechanisms responsible for their fluoroquinolone (FQ) resistance. These isolates were analyzed for clonal similarity, mutations in genes encoding the FQ targets, overexpression of specific Resistance Nodulation-cell Division efflux pumps, and search for mutations in their regulatory genes. The achieved results suggested that the mutations in genes encoding ciprofloxacin targets represented the main mechanism of FQ resistance of these strains; 97.8% of these isolates showed mutations in gyrA, 28.9% in gyrB, 88.9% in parC, and 6.7% in parE. Another mechanism of resistance was overexpression of the efflux pumps in some representative strains. In particular, overexpression of MexXY-OprM drug transporter was found in five isolates, whereas overexpression of MexCD-OprJ was detected in two isolates; surprisingly, in one of these last two isolates, also overexpression of MexAB-OprM pump was identified.
AB - Efflux transporters have a considerable role in the multidrug resistance (MDR) of Pseudomonas aeruginosa, an important nosocomial pathogen. In this study, 45 P. aeruginosa clinical strains, with an MDR phenotype, have been isolated in a hospital of Northern Italy and characterized to identify the mechanisms responsible for their fluoroquinolone (FQ) resistance. These isolates were analyzed for clonal similarity, mutations in genes encoding the FQ targets, overexpression of specific Resistance Nodulation-cell Division efflux pumps, and search for mutations in their regulatory genes. The achieved results suggested that the mutations in genes encoding ciprofloxacin targets represented the main mechanism of FQ resistance of these strains; 97.8% of these isolates showed mutations in gyrA, 28.9% in gyrB, 88.9% in parC, and 6.7% in parE. Another mechanism of resistance was overexpression of the efflux pumps in some representative strains. In particular, overexpression of MexXY-OprM drug transporter was found in five isolates, whereas overexpression of MexCD-OprJ was detected in two isolates; surprisingly, in one of these last two isolates, also overexpression of MexAB-OprM pump was identified.
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U2 - 10.1089/mdr.2011.0019
DO - 10.1089/mdr.2011.0019
M3 - Article
C2 - 21797666
AN - SCOPUS:84856707767
VL - 18
SP - 23
EP - 32
JO - Microbial Drug Resistance
JF - Microbial Drug Resistance
SN - 1076-6294
IS - 1
ER -