BIOFILM FORMATION BY PSEUDOMONAS AERUGINOSA STRAINS WITH DIFFERENT LEVELS OF CYCLIC DI-GUANOSINE MONOPHOSPHATE BIOSYNTHESIS

Aim: Swarming motility and biofilm formation abilities determination in P. aeruginosa PA01 pJN2133, with low c-di-GMP level. Materials and methods. P. aeruginosa PA01 and P. aeruginosa PA01 pJN 2133 were used as a test-organisms. Bacteria were cultivated in 24-walls Nuclon plates in LB medium at 37 °С for 30–60 min for adhesion determination and for 24 hours for biofilm formation. Determination of planktonic cells amount were carried out spectrophotometrically, biofilm formation – by CV-test, and polysaccharide determination – by alcian blue and congo red staining. Swarming motility, hydrophobicity, and z-potential were carried out by common methods. Results. It was shown that P. aeruginosa PA01 pJN2133 form biofilm with impaired structure and in 3.7 times less intensive than P. aeruginosa PA01. Even on early stages of the biofilm formation mutant strain shows low ahession ability compare to wild type. P. aeruginosa PA01 pJN2133 planktonic cells amount was higher than in wild type strain at all stages of biofilm formation. P. aeruginosa PA01 pJN2133 swarming motility zones diameter was 62 ± 5 mm and it was in 1.4 times higher than at P. aeruginosa PA01 – 43 ± 3 mm. Swarming motility zones morphology were different. It was shown that cells of each strains change its hydrophobicity from logarithmic to stationary phase, but direction of changes was opposite. P. aeruginosa PA01 pJN2133 cells hydrophobicity increase at stationary phase. P. aeruginosa PA01 cells hydrophobicity were higher in logarithmic phase. Cells of each strains have the same z-potential. Conclusions. On the frame of low c-di-GMP amount P. aeruginosa PA01 pJN2133 have low adhesion and biofilm formation abilities. Planktonic cells amount and swarming motility intensity are conversely high.