[Obtaining of intrapopulational dissociants of some bacilli and the use of DIR-PCR for their identification].

The paper is the first to suggest methods for rapid obtaining and genotypic identification of phenotypic (colonial-morphological) dissociants of bacterial cultures. For revelation of the potential dissociation ability and obtaining of dissociants, the use of bacterial cyst-like refractile cells (CRC) is recommended. These cells are characterized by enhanced variability; upon their first passage, an abrupt increase in the dissociation index is observed as a result of the emergence of cells that form morphologically different types of colonies. The approaches elaborated were tested with Bacillus cereus, B. subtilis, and B. licheniformis, for which colonial-morphological dissociants of various types were obtained after the first passage of CRC (both of those formed in the developmental cycle of bacteria and of those arising as a result of artificial increase of the concentration of anabiosis autoinducers in the cultivation medium). The genomic distinctions between dissociants of B. cereus and B. subtilis were estimated using polymerase chain reaction with a primer system designed based on the analysis of nucleotide sequences of complete prokaryotic genomes available in the GenBank database (DIR-PCR). The application of the suggested method allowed distinctions between the genomes of dissociants of Bacillus cereus and B. subtilis to be revealed, which is in agreement with the hypothesis that suggests reversible intragenomic rearrangements to be the basis of bacterial dissociation into subpopulations.