THE STUDY OF THE ANTAGONISTIC ACTIVITY OF BACTERIA SUPPRESSING THE SYNTHESIS OF PHENAZINES PSEUDOMONAS AERUGINOSA

Abstract

The purpose of the study was the search for microorganisms capable of suppressing quorum feelings associated with the production of phenazines (pyocyanin). The formation of pyocyanine, related to oxyphenazines, is one of the indicators of the quorum-sensing reaction. In order to search for antagonistically active bacterial strains, the microorganisms were co-cullured with the cultures of Pseudomonas aeruginosa wherein the suppression of oxyphenazine production was determined. We used 14 cultures of bacteria from the genera Pseudomonas, Acinetobacter, Enterobacter, Staphylococcus, Microbacterium, Serratia, Sphingobacterium, Lactobacillus, Weisella to find strains suppressing the production of pyocyanin. Piocanin was successively extracted with chloroform and 0.2 M hydrochloric acid, after which its content was determined spectrophotometrically at a wavelength of 520 nm. Several bacterial cultures characterized by the ability to inhibit the production of oxyphenazine in co-cultivation tests with Pseudomonas aeruginosa were found. The identified microorganisms belonged to the microorganisms of the genera Acinetobacter and Pseudomonas, Lactobacillus and Weisella. The Kruskal-Wallis criterion - H (5, N = 21) = 11.86902 is statistically significant (p = 0.0366). The distribution of cultures in the inhibition of the production of oxyphenazines in the experiments on co-cultivation with Pseudomonas aeruginosa was not binomial, which implies the non-random nature of the distribution of cultures according to the results of co-cultivation. Thus, the levels of inhibition of the production of phenazines for different taxa of bacteria in the co-cultivation tests were statistically significantly different from each other. The largest sum of ranks belongs to the group Lactobacillus spp. and this taxon has the greatest effect on the content of phenazines. The decrease in the concentration of fhe final product (pyocyanin), the synthesis of which is initiated by butanol-homoserine lactone, can be associated with the mechanisms of quorum-quenching, and the mechanisms of antagonistic activity of microorganisms that affect the production of the aforementioned metabolites of P. aeruginosa.