There were considered molecular, physiological-biotechnical and morphological features of R-. R-, S- and M-dissociates of Pseudomonas Aeroginosa. For all three dissociates, 100 % of the sequence similarity of the fragments of their genes encoding 16S pPNC. Using a number of methods, dissociates compared the ways of using glucose. In R-cells respiration prevailed, in M-cells – fermentation with formation of formic acid, which lead to the ability of cells to grow in the anaerobic conditions, in S-cells observed switching from one glucose pathway to another. The determination of the resistance of bacteria to the action of external factors showed that R-dissociate had selective advantage with an increase in temperature of the growth, UV irradiation and storage, M-dissociate with the lowering of the temperature of cultivation and an increase of the osmotic pressure. The use of sub inhibitory concentrations of substances used to suppress the development of biofilms leads to stimulation of growth of these biofilms increase in the proportion due to advantageous increase in the proportion of thick-walled and rapidly growing R-cells.

The ability of purple photosynthetic bacteria to form phase variants (dissociants) was discovered. The R and M phase variants were isolated from the Rhodobacter sphaeroides population, and their affiliation with the parent strain was confirmed by the PCR of their 16S rRNA gene fragments. The R and M variants were different both in colony morphology and in resistance to some physical and chemical factors. The R variant of Rhb. sphaeroides had advantages when grown in the light, at elevated temperature, under aeration, and UV irradiation, whereas the M variant had advantages when grown aerobically in the dark or at increased NaCl concentrations.