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Introduction. The study of the ability of Bacillus anthracis strains with different phenotypic properties to spore germination, reproduction and sporulation on a medium based on an aqueous soil extract can help assess the significance of these processes in the formation and maintenance of soil anthrax foci. Aim. The analysis of individual characteristics of the development of a vegetative culture of anthrax pathogen strains with different phenotypes in a soil medium model. Materials and methods. On a group of anthrax microbe strains with different plasmid composition and virulence, the possibility of spore germination, reproduction of bacilli and, at least in some of them, productive spore formation on the soil medium was studied. Results. Three variants of culture development of B. anthracis strains were identified: 1 spores remain intact, not germinating; 2 after germination of spores, bacilli are formed, which multiply with different intensity, passing into involutional forms without spore formation; 3 the passage of a complete physiological cycle "sporebacillusspore". The presence of 2% blood in the soil environment contributed to the germination of spores and reproduction of the culture, but inhibited the process of sporulation during the observation period of 3 days. No correlation was found between a certain phenotype of the studied strains of B. anthracis and the ability to germinate and vegetate on soil media. Conclusion. The data obtained that only 17% of CFU gives rise to the formation of colonies on the soil medium suggest the heterogeneity of the properties of the population of the studied strains. Isolation of such cultures and their further detailed study will make it possible to identify the most significant complexes of biological properties for the realization of a complete physiological cycle under soil-simulating conditions.

Introduction. The study of the protein composition of the causative agent of anthrax — Bacillus anthracis, allows you to identify both general species and individual characteristics of strains that differ in phenotypic properties, manifested mainly in the vegetative form and which are important for virulence, immunogenicity and the ability to adapt to different vegetation conditions.Purpose of the work. In the group of anthrax microbe strains having different plasmid composition and virulence, different methods of extraction of the total proteome from vegetative bacillus cells have been tested.Results. In the course of the work, it was shown that the rate of spore formation varies significantly between individual strains of the anthrax microbe and can have a significant impact on the efficiency of extraction and the composition of the protein complex. Preliminary treatment with lysozyme, which affects the cell membrane, promotes a more complete lysis of cells, and ultramicrocentrifuge filtration provides complete specific sterility of the obtained samples.Conclusion. A culture preparation scheme was developed for B. anthracis, which allows one to obtain a culture in the vegetative phase of the life cycle and to efficiently extract proteins in combination with reliable disinfection of samples.

A decrease in therapeutic effect of some live lacto- and bifdobacteria-based drugs for veterinary use has been observed for the last 20 years that urges scientists to search for new microorganisms possessing probiotic properties. Many studies in this feld are focused on Bacillus subtilis that is widespread in the environment and non-pathogenic for animals and humans. Results of tests of Bacillus subtilis for its biological properties and antagonistic activity aimed at optimization of methodical approaches for detection of strain with the highest antagonistic effect on some opportunistic microorganisms and their further use as probiotics are described. Cultural morphological and biochemical characteristics of the tested strains conformed to the species characteristics of Bacillus subtilis. Tested strains were nonpathogenic for white mice. Tests showed that spore biomass could be prepared both in liquid and on solid nutrient media. Methodically, spore biomass preparation in liquid nutrient medium is preferable. The tests showed that spores emerged from anabiosis non-uniformly and it depended on original seed spore storage period. Spore cultures stored less than one year emerged from anabiosis more quickly. It was found that the spores formed more readily when the cultures were aerated with oxygen as well as that lag-phase culture medium had a stimulating effect on Bacillus subtilis spore germination. Bacillus subtilis strains were found to have antagonistic effect on Escherichia coli, Salmonella and Staphylococcus. Area of growth inhibition of the said bacteria was 15–20 mm. Tested Bacillus subtilis strains could be proposed for use as probiotics.