| Abstract [eng] |
Antibiotic resistance is one of the main factors causing difficulties in treatment of bacterial infections. Several mechanisms are known to be responsible for this resistance, including target alteration, enzymatic modification of antibiotics, low cell envelope permeability and active efflux of toxic compounds. The latter mechanism is considered to play a major role in bacterial antibiotic resistance. In this study a method for real-time efflux pump activity evaluation has been developed. Importantly, in contrast to other methods, neither radio-labeled nor toxic compounds are used in this method. Moreover, bacterial suspension is thermostated and aerated throughout the assay. Tetraphenylphosphonium (TPP+) ions and TPP+-selective electrodes were used to evaluate the activities of tetracycline-specific TetA(B) and multiple drug resistance pumps (MDR) in E. coli and P. aeruginosa, respectively. It was shown that TetA(B) can effectively expel not only tetracycline but also TPP+. Optimal conditions for evaluation of the activities of MDR efflux pumps in P. aeruginosa were determined. The developed method can be applied to study the interactions between the efflux pump inhibitors and their cellular targets. Moreover, this method can be applied to monitor the differences in efflux pumps’ activities among clinical isolates. |
