[Monitoring of life-threatening infection pathogens in relation to the problem of prediction of critical situations]. / Monitoring vozbuditelei opasnykh infektsii v sviazi s problemoi prognozirovaniia kriticheskikh situatsii.

The epidemic situation in the context of many infectious diseases caused by bacteria is presently assessed as being poor in Russia and other countries. The spectrum of the pathogens that can deteriorate epidemic well-being is highly wide. The epidemic situation in terms of many infectious diseases, including those caused by such causative agents as Bacillus anthracis, Vibrio cholerae, Yersinia pestis, Francisella tularensis and others may deteriorate due to the emergence of their modified forms owing to their specific variability. The above generates the necessity of improving controlling measures or developing the techniques for monitoring the pathogens of infectious diseases, including those in the framework of international cooperation.

[Molecular mechanisms underlying bacillus anthracis infection at early stages and search for novel vaccines]. / Molekuliarnye mekhanizmy nachal'nykh étapov sibireiazvennoí infektsii i poisk novykh vaktsin.

The developmental mechanisms of anthrax immunity were studied. Immunization was found to generally generate specific antibodies and lysozyme. Collectively, all the factors are responsible for suppressing the development of spores in the body. This proves the fact that the immunity is directed not only towards the exotoxin of B. anthracis, but it affects mainly the formation of vegetative cells. On entering the immuned body, vegetative cells may cause B. anthracis infection because antitoxic antibodies have no effect on encapsulated cells. The findings indicate that any anti-anthrax vaccine strain must show a complete immunological response in the body, as well as constitute immunity to all pathogenetic factors of B anthracis.

[Behavior of heterologous recombinant plasmid pCET in cells of Bacillus anthracis]. / Povedenie geterologichnoi rekombinantnoi plasmidy pCET v kletkakh Bacillus anthracis.

Recombinant plasmid pCET was constructed in vivo in cells of enteric and hay bacillus, on the basis of plasmids pC194, and pBC16. Plasmid pCET inherits marker genes of antibiotic resistance from parental plasmids. Anthrax cells were transformed by the recombinant plasmid developed. The behavior of this plasmid was studied in vegetative Bacillus anthracis cells, which did not pass through the sporulation stage and were cultivated at temperatures permissive for the replicon of plasmid pE194. Under these conditions, plasmid pCET was shown to replicate autonomously, regardless of the host chromosome, and to retain its structure, irrespective of the recipient strain. In this case, the phenotype of transformants fully corresponded to the genotype of plasmids inherited. Elevation of the cultivation temperature of strains Bac, anthracis (pCET) up to 44 degrees C led to the elimination of plasmid pCET from cells of anthrax microbe under conditions nonselective for plasmid pCET and its integration with the host chromosome under selective conditions. The frequency of plasmid pCET integration into the chromosome was approximately 10(-1) for all Bac. anthracis strains studied. In population of vegetative cells of strains Bac. anthracis (pCET), which passed through the sporulation stage under selective for plasmid pCET conditions, DNA of plasmid pCET was detected only in the state integrated with the chromosome. Irrespective of the reasons leading to the integration of plasmid pCET into the Bac. anthracis chromosome, all strains inheriting this DNA within their own genome lost the resistance to tetracycline observed in strains with the extrachromosomal plasmid location. Genome amplification of plasmid pCET in the chromosome of Bac. anthracis was detected.