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Showing 3 results for Efflux Pump

Mohsen Heidary, Aghil Bahramian, Hossein Goudarzi, Gita Eslami, Ali Hashemi, Saeed Khoshnood,
Volume 19, Issue 4 (7-2016)
Abstract

Background: The efflux pumps are one of the main mechanisms of resistance to antibiotics in E. coli and K. pneumoniae strains. The aim of this study is to study the association between genes coding efflux pumps AcrAB and Qep A and ciprofloxacin resistance among E. coli and K. pneumoniae clinical strains

Materials and Methods: This study was done on 100 strains of E. coli isolated from Taleghani and Labbafinejad Hospitals and 100 strains of K. pneumoniae isolated from Taleghani and Mofid Children Hospitals. Antimicrobial susceptibility tests were performed by disk diffusion method based on CLSI guidelines. Identification of genes encoding efflux pumps Acr AB and Qep A was done by PCR technique.

Results: In this study, fosfomycin and imipenem had the best effect against E. coli clinical isolates and fosfomycin and tigecycline had the best effect against K. pneumoniae clinical isolates. PCR assay demonstrated that the prevalence of AcrA, AcrB and QepA genes among E. coli isolates were 92%, 84% and 0%, respectively and among K. pneumoniae isolates were 94%, 87% and 4%, respectively.

Conclusion: The prevalence of genes encoding efflux pumps in E. coli and K. pneumoniae clinical strains, which causes resistance to fluoroquinolones, is cause for concern. Therefore, controlling infection and preventing the spread of drug-resistant bacteria needs to manage medication carefully and identify resistant isolates.


Maryam Doosti Mohajer, Hamid Pajavand, Ramin Abiri, Amirhooshang Alvandi,
Volume 20, Issue 9 (12-2017)
Abstract

Abstract
Background: Antibiotic resistance rates in E. coli are rapidly rising, especially with regard to fluoroquinolones. One of the mechanisms that lead to antibiotic resistance is efflux pumps. The aim of this study was phonotypic and genotypic analysis of efflux pump role in fluoroquinolones resistance of E. coli strains isolated from hospitalized patients in Kermanshah 2013.
Materials and Methods: In this cross-sectional study, 100 isolates of E. coli were collected from hospitalized patients from Kermanshah. All isolates were identified by standard biochemical tests. The antimicrobial susceptibility patterns were determined by disk diffusion method according to CLSI guidelines. The presence of Efflux pump genes was determined by a PCR method.
Results: The rates of resistance to Ceftazidime, Nalidixic Acid, Ciprofloxacin, Norfloxacin, Ofloxacin, Gentamicin, and Tetracycline were 73%, 67%, 55%, 54%, 45%, 38%, and 24%, respectively. According to the results of PCR test, of 100 E. coli isolates, 99% of isolates were positive for acrA, 98% for acrB, 95% for acrE, 98% for acrF, 94% for mdfA, 96% for norE, and 96% for tolC.
Conclusion: In Strains with positive gene acrA, acrB, acrA, acrB, tolC, mdfA, norE, the presence of efflux pump inhibitor reduced the amount of resistance to antibiotics. So, efflux pumps are important in antibiotic resistance.

 

Ahmad Sahabzamani, Dr. Maryam Sadrnia, Dr. Majid Akbari, Dr. Sasan Saki,
Volume 25, Issue 3 (8-2022)
Abstract

Background and Aim The efflux pump in Pseudomonas aeruginosa inhibits the effect of ciprofloxacin by releasing quinolones out of the cell. It is important to find compounds to inactivate or inhibit its activity to continue using the antibiotics. The present study was done to investigate using sertraline as an efflux pump inhibitor in P. aeruginosa to reduce antibiotic resistance.
Methods & Materials P. aeruginosa strains were isolated from clinical sources and identified by routine microbiological methods. Resistance of the isolates to ciprofloxacin was evaluated by Kirby–Bauer test. Resistance breakdown was investigated by adding sertraline to the Moller Hinton agar medium and determining the zone of inhibition of ciprofloxacin. Minimum inhibitory concentration (MIC) by microplate dilution method and Minimum bactericidal concentration (MBC) by culture and MTT method were done for the isolates and ATCC 27853. The presence of the efflux pump was evaluated by the phenotypic method using sertraline and serial dilution method of the liquid medium in a microplate, on ciprofloxacin-resistant strains. The presence of the producing gene of this pump was determined by the genotyping method in resistant strains by performing PCR. The standard PAO1 strain of P. aeruginosa was used as a positive control.
Ethical Considerations This study was approved by the Ethics Committee of the Faculty of Medical Sciences of Islamic Azad University, Brojerd Branch (Code: IR.IAU.B.REC.1401.011).
Results Based on Kirby–Bauer test results, three strains were considered resistant to ciprofloxacin. MIC of drug-resistant strains was between 32 and 64 mg/ml and MBC was between 16 and 32 mg/ml. By performing electrophoresis on the PCR products, it was determined that the tested strains contained the mexA gene encoding the efflux pump. In the agar medium without sertraline, the zone of inhibition around the ciprofloxacin disc was zero, but after adding sertraline, the diameter of the halo increased to 25 mm. The minimum inhibitory concentration of ciprofloxacin in the isolates before adding 25 µg of sertraline was 128 µg/ml and after adding sertraline, it was 4 µg/ml.
Conclusion It was concluded that sertraline inhibited the efficiency of the efflux pump in resistant P. aeruginosa isolates and reduced ciprofloxacin resistance.


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