On the interactions of Yersinia strains and cell cultures.

Comparative investigations were carried out on the dynamics of invasion of cell cultures by strains Yersinia pestis EV and Yersinia pseudotuberculosis treated vitally with petroleum ether. It was established that the invasiveness of the strains studied was related to the presence of chemical structures of the bacterial surface sensitive to the action of either and whose synthesis was temperature dependent. The penetration and initial stages of intracellular multiplication of the Yersinia were accompanied with a certain activation of the RNA- and protein-syntheses in the host cells. That was clearly expressed in cell populations inoculated with Yersinia variants of high invasiveness. After the 24th hour of inoculation of the cell cultures a decrease of the rate of metabolic processes in invaded cells was observed due to the destructive changes in their cytoplasm. At the end of the investigation it reached values considerably lower than those of the controls.