Electron-Microscopic Investigation of Interactions between <I>Yersinia pseudotuberculosis</I>, <I>Yersinia pestis</I> Cells and Specific Bacteriophages

Carried out has been electron-microscopic investigation of dynamics of interactions between Yersinia pseudotuberculosis, Yersinia pestis cells and specific bacteriophages in vitro. Identified have been peculiarities in morphological manifestation of the interactions. Determined are morphometric characteristics of the bacteriophages utilized in the experiment. It is demonstrated that after 40 minutes of co-incubation of Y. pseudotuberculosis with specific bacteriophage emergence of persisting forms of microbial cells is observed, while in case of EV strain infecting with Pokrovskaya bacteriophage, this phenomenon is not detected

Effect of Bacteriophages and Gentamycine on Morphology and Vesicle Formation of Bacteria Yersinia pestis EV

Objective was to assess the effect of specific bacteriophages and gentamycine on the morphological-functional properties of bacteria in the vaccine strain Yersinia pestis EV.Materials and methods. The vaccine strain Y. pestis EV, Pokrovskaya bacteriophage and the pseudotuberculous diagnostic bacteriophage were used for the study. The microbial culture was grown on solid and in liquid growth media at 27 °C for 20–24 h. The co-incubation of bacteria and bacteriophage or gentamycine was carried out at 27 °C for 20 minutes or at 37 °C for 2 hours, respectively. Culture preparations were examined by transmission electron microscopy.Results and discussion. The influence of cultivation conditions and various stress factors on the vesicle production by the vaccine strain Y. pestis EV cells was evaluated. The nature and intensity of morphological-functional changes in Y. pestis EV cells in response to the effect of bacteriophages (plague Pokrovskaya and pseudotuberculous bacteriophages) or an antibiotic (gentamycine) were determined. It was established that co-incubation of Y. pestis EV with Pokrovskaya bacteriophage or gentamycine for 20 min leads to the increase in the production of extracellular vesicles and is accompanied by the development of degenerative changes in bacterial cells

IMMUNOCHEMICAL STUDY OF RECEPTION OF PLAGUE BACTERIOPHAGE POKROVSKY

Aim. Study of mechanism of reception of plague bacteriophage Pokrovsky to cells of Yersinia pestis using a panel of monoclonal antibodies. Materials and methods. Using a method of competitive inhibition, the ability of monoclonal antibodies against antigenic epitopes of outer membrane of Yersinia genus bacteria to inhibit adhesion of the studied bacteriophage to cells of Y. pestis EV strain, was evaluated. Results. A key role of structure of carbohydrate nature in reception of Pokrovsky bacteriophage was confirmed. Among 5 lines of monoclonal antibodies against protein epitopes 2 were established to cause significant inactivation of bacteriophage adhesion to bacterial cells. Conclusion. An assumption is proposed regarding participation of a structure of polypeptide nature in reception of Pokrovsky bacteriophage by cells of plague microbe