[Highly repetitive elements in the genome of plague pathogen].

Y. pestis high repeated sequences DNA (HRS) used as probes in the blot hybridization procedure made it possible to reveal some tendencies of their location on the chromosome, namely, the correlation with the regions where Y. pestis strains were isolated, correlation with the stability of their properties and, perhaps, with the variation of individual strains.

[Changes in the antimicrobial potential of the phagocytosing cells of great gerbils in experimental plague].

The work deals with the results obtained in the study of the activity of the cytocidal systems of phagocytes in great gerbils under normal conditions and during the plague infectious process. The data have been analyzed in comparison with the corresponding characteristics of phagocytic activity in mice. Changes in the oxygen-dependent metabolism (ODM) of neutrophils and macrophages, responsible for the functioning of their oxygen-dependent cytocidal systems, in plague show features characteristic of the nonspecific systemic postaggression reaction (SPAR).

[Characteristics of the polysaccharide-containing somatic antigens isolated from the K-1 strain of the plague microbe and its antibiotic-resistant variants].

Immunochemical analysis of 2 polysaccharide-containing structures of the lypopolysaccharide of the plague causative agent (main somatic antigen and lipopolysaccharide) isolated from K-1 strain and a number of its antibiotic resistant mutants was carried out. It was shown that development of resistance to streptomycin alone or its combination with monomycin did not cause detectable changes in the monosaccharide composition and serological properties of the cultures tested. More significant changes associated with development of complex resistance, i.

[Sensitivity of repair-defective mutants of the plague microbe to the action of physical and chemical agents].

By the character of the sensitivity of UV-irradiation, to N-methyl-N'-nitro-N-nitrosoguanidine, 5-bromuracil, mitomycin C, crystalviolet, and by the capacity to restore phage injuries the 1435-A and 1435-24 mutants were referred to the uvr-hcr-, 17 mutant--to the uvr-hcr+, and 35 mutant--to lon genotype. As a result of UV irradiation the experimental strains formed heteromorphic forms of bacteria, spindle-shaped, filamentous cells, were sensitive to the action of static electrical field of high frequency, this pointing to disturbance of cellular membranes structure in these mutants.