Creation of Pyocin Composition Against Laboratory and Clinical Pseudomonas aeruginosa Strains

Pseudomonas aeruginosa belongs to the group of ESKAPE pathogens, which most often cause nosocomial infections and are characterized by a high level of antibiotic resistance. Bacteriocins are considered to be one of the promising substances that can be used as an additional means of influencing P. aeruginosa strains with multiple antibiotic resistance. The aim of this work was to evaluate the possibility of creating an effective composition from the minimum quantity of pyocins capable of inhibiting the growth of laboratory and clinical P. aeruginosa strains. Methods. The object of the study was P. aeruginosa bacteriocins (pyocins) isolated from 10 highly active producers. Analysis of pyocin’s activity and subsequent selection of the composition were carried out after assessing its influence on 51 cultures, which included laboratory strains, isolated from plant cultures, and clinical P. aeruginosa strains. Results. It was established that according to activity spectrum of the studied bacteriocins, pyocins 335, 333, 330, 13, and 332 can be referred to the most promising. To inhibit the growth of laboratory P. aeruginosa strains, it is sufficient to use pyocins 335 and 333 added with a third pyocin into the composition – 13 or 332. As for cultures isolated from plants, only pyocins 330 and 332 were characterized by high activity. In contrast, most pyocins influenced clinical isolates, which were multidrug-resistant to widely used antibiotics. The average activity of the selected pyocin composition 332+333+335 against laboratory cultures was 204.8×103 AU/mL and against clinical strains – 153.6×103 AU/mL. Conclusions. Thus, for the first time, the possibility of creating an effective composition of three pyocins that is capable of affecting both laboratory and clinical P. aeruginosa strains has been shown. The most optimal combination includes pyocins 332, 333, and 335, which contain S1, S2, S4, S5, and S9 bacteriocin subtypes. These substances do not exhibit mutual antagonism, bind to different receptors, and, due to DNase, tRNase, and pore-forming activities, inhibit the growth of all 51 cultures studied, represented by laboratory and isolated from plant strains, as well as clinical multidrug-resistant P. aeruginosa isolates.