Inchagova X.S., Galadzhieva A.A.
THE INFLUENCE OF KANAMYCIN AND DOXYCYCLINE ANTIBIOTICS ON N-BUTYRYL-L-HOMOSERINE LACTONE AUTOINDUCER EXPRESSION IN CLINICAL ISOLATES OF PSEUDOMONAS AERUGINOSA ^{[№ 9 ' 2016]}
Pseudomonas aeruginosa is one of the major causative agents of nosocomial infections. An important feature of this pathogen is the formation of biofilms and numerous secreted virulence factors controlled by the density-dependent chemical communication system (named «quorum sensing»). The way to the suppression of «quorum sensing» is a topical aspect of pseudomonas infection improved treatment. We used four clinical isolates of Pseudomonas aeruginosa, isolated in the maternity hospitals of Orenburg region and exhibiting the ability to synthesize a key «quorum sensing» autoinducer — N-butyryl-L-homoserine lactone (C₄-AHL). The sub-MIC concentration of tested antibiotics showed a regulatory effect on this ability that was different for aminoglycosides (kanamycin sulfate), and tetracyclines (doxycycline hydrochloride). The kanamycin led to suppression of C₄-AHL expression that indicate an autoinducer biosyntesis pathway as a target for this antibiotic. In turn, the effect of doxycycline was the accumulation of extracellular C₄-AHL, indicating a violation of the autoinducer reception in bacterial target cells. The revealed regulatory activity of aminoglycosides and tetracyclines on the «quorum sensing» system have described these antibiotics as a regulators of the density-dependent chemical communication system in pathogenic bacteria, which showed new possibilities for their use in the treatment of P. aeruginosa infections.