• List of Articles ژن gyrB

      • Open Access Article

        1 - Assessment of point mutations associated with ciprofloxacin resistance in Pseudomonas aeruginosa isolates in Guilan province
        Najmeh Ranji Fatemeh Asadi Rahmani Seyedeh Shideh PourKhalili
        Background & Objectives: Pseudomonas aeruginosa is an opportunistic pathogen especially in immunocompromised patients. Drug resistance in P. aeruginosa is caused by different mechanisms such as mutations in topoisomerases subunits and negative regulators of efflux p More
        Background & Objectives: Pseudomonas aeruginosa is an opportunistic pathogen especially in immunocompromised patients. Drug resistance in P. aeruginosa is caused by different mechanisms such as mutations in topoisomerases subunits and negative regulators of efflux pump systems. This study was aimed to investigate mutations in gyrB, parC, and nfxB genes in ciprofloxacin-resistant P.aeruginosa isolates in Guilan province.   Materials & Methods: In this cross-sectional study, 200 isolates were obtained from different clinical samples of Rasht and Lahijan hospitals and laboratories and subsequently identified by biochemical tests. Antibiotic susceptibility pattern was determined by Kirby Bauer disk diffusion susceptibility test and Minimum Inhibitory Concentration (MIC) test. PCR-sequencing was used to assess mutations in gyrB, parC, and nfxB genes in ciprofloxacin-resistant P. aeruginosa isolates.   Results: Out of  69 P. aeruginosa isolates, 26 isolates were ciprofloxacin-resistant. MIC of ciprofloxacin in resistant isolates was determined between 32-1024 µg/ml. PCR-sequencing analysis revealed that some resistant isolates have missense mutations in gyrB, parC, and nfxB genes. It seems that N368S, I424L, L464I, E468D, M520L, and I524V mutations in gyrB were reported for the first time in Iran.   Conclusion: It seems that reported mutations in gyrB and parC genes affect topoisomerases affinity to ciprofloxacin in resistant isolates. Furthermore, mutations in the nfxB gene may lead to overexpression of MexCD-OprJ efflux pump and ciprofloxacin resistance.   Manuscript profile
      • Open Access Article

        2 - Determination of antibiotic susceptibility pattern of Pseudomonas aeruginosa and the prevalence of bla OXA-23 gene in isolates from a Hospital in North Khorasan
        Mohadeseh Radmehr majid moghbeli
        Background & Objectives: Pseudomonas aeruginosa is one of the most important pathogens of opportunistic infections, which is considered as one of the main causes of nosocomial infections. The aim of this study was to isolate pseudomonas aeruginosa and identify strai More
        Background & Objectives: Pseudomonas aeruginosa is one of the most important pathogens of opportunistic infections, which is considered as one of the main causes of nosocomial infections. The aim of this study was to isolate pseudomonas aeruginosa and identify strains with                  bla OXA-23 gene using polymerase chain reaction (PCR) technique. Materials & Methods: In this study, 70 isolates of pseudomonas aeruginosa from various            infections including lung, urine, blood, wound and sputum were collected in north khorasan       hospital, after phenotypic and genotypic confirmation of the isolates, antibiotic discs of doripenem and imipenem (Rosco), meropenem and ciprofloxacin, colistin and amikacin (Mast) were used to perform antibiotic susceptibility testing of bacteria by disk diffusion method. Results: Isolates showed 32.8%, resistance to amikacin , 47.1% todoripenem, 37.1% to imipenem, 40% to ciprofloxacin, and 10% to colistin. The highest resistance of the strains was related to meropenem 61.4% and the lowest was colistin with 10% resistance. Conclusion: In this study, the resistance of pseudomonas aeruginosa to the antibiotic meropenem was 61.4% and compared to other studies, including in ethiopia, showed a higher level of           antibiotic resistance, this level of carbapenem resistance indicates an increase in resistance of pseudomonas aeruginosa strains to carbapenems.   Manuscript profile