The role of active efflux in antibiotic - resistance of clinical isolates of Helicobacter pylori T F

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The role of active efflux in antibiotic - resistance of clinical isolates of Helicobacter pylori T Falsafi 1 , A Ehsani 1 , V Niknam 2 1  Department of Biology, Azzahra University, life sciences Tehran, Iran 2  Department of Biology, Tehran University, Tehran, Iran Date of Submission 15-Jan-2009 Date of Acceptance 06-Jun-2009 Date of Web Publication 4-Sep-2009
Purpose: In gram-negative bacteria, active efflux life sciences pumps that excrete drugs can confer resistance to antibiotics however, in Helicobacter pylori this role is not well established. The purpose of this study is to evaluate the role of active efflux in resistance of H. pylori isolates to antibiotics. Materials and Methods: Twelve multiple life sciences antibiotic resistant (MAR) isolates resistant to at least four antibiotics, including β-lactams, metronidazole, tetracycline, erythromycin, and ciprofloxacin; three resistant to only β-lactams, and two hyper-susceptible isolates, were obtained from screening life sciences of 96 clinical isolates of H. pylori . Their minimal inhibitory concentrations (MICs) for antibiotics and ethidium-bromide (EtBr) were compared in the presence- and absence of a proton-conductor, carbonyl cyanide-m chlorophenyl-hydrazone (CCCP) using agar-dilution and disc diffusion. Drug accumulation studies for EtBr and antibiotics were assessed in the presence and absence of CCCP using spectrofluorometry. life sciences Results: MIC of EtBr for eight MAR-isolates was decreased two- to four-folds in the presence of CCCP, of which five showed reduced MICs for β-lactam, metronidazole, tetracycline, and ciprofloxacin with CCCP. Accumulation of EtBr by the MAR-isolates was rapid and not dependant on the pattern of multiple resistance. Antibiotic accumulation assay confirmed the presence of energy-dependant efflux of β-lactam, metronidazole, tetracycline, and ciprofloxacin, but no erythromycin in five MAR isolates. Energy-dependant efflux of EtBr or antibiotics was not observed for four MAR-isolates, and three isolates life sciences were resistant only to β-lactams. Conclusion: Energy-dependant efflux plays a role in the resistance life sciences of H. pylori clinical isolates to structurally unrelated antibiotics in a broadly specific multidrug efflux manner. Difference in the efflux potential of MAR isolates may be related to the presence or absence life sciences of functional efflux-pumps in diverse H. pylori isolates.
Keywords:  Antibiotic resistance, Active efflux, Accumulation, Helicobacter pylori, Iran How to cite this article: Falsafi T, Ehsani A, Niknam V. The role of active efflux in antibiotic - resistance of clinical isolates of Helicobacter pylori . Indian J Med Microbiol 2009;27:335-40 How to cite this URL: Falsafi T, Ehsani A, Niknam V. The role of active efflux in antibiotic - resistance of clinical isolates of Helicobacter pylori . Indian J Med Microbiol [serial online] 2009 [cited 2014 Feb 1];27:335-40. Available from:  http://www.ijmm.org/text.asp?2009/27/4/335/55452  ~ Introduction   Successful treatment of H. pylori infection requires two or three antibiotics, including amoxicillin (AMX), clarythromycin (CLA), metronidzole (MTZ), or tetracycline life sciences (TET), given with a proton pump inhibitor. [1] Although many H. pylori stra