[Peculiazities Growth of Bacteria Azotobacter vinelandii IMV V-7076 and Bacillus subtilis IMV V-23 in Pure and Mixed Cultures at Submerged Cultivation]

The features of the growth of Azotobacter vinelandii IMV V-7076 and Bacillus subtilis IMV V-7023 in optimized environments in single and mixed culture at deep cultivation to simulate the accumulation stage (capacity) biomass biotechnology creation of complex bacterial preparation for crop production. When growing Bacillus subtilis IMV B-7023 in monoculture specific growth rate of the bacteria was higher than that of Azotobacter vinelandii IMV B-7076. Therefore, by cultivating a mixed culture medium in the fermenter was inoculated with the bacterial suspension A. vinelandii + B. subtilis in a ratio of 10 : 1. The greatest biomass accumulation was observed after 24 hours of cultivation of mixed cultures. Spent submerged culture A. vinelandii IMV B-7076 and B. subtilis IMV B-7023 in the fermenter can be recommended for suspension of high-viable cells of both strains in biotechnology industrial manufacturing complex bacterial preparation for crop production.

Impact of a Number of Factors on Physiological and Biochemical Activity of Strains ­ Components of Azogran, a Complex Bacterial Preparation.

The use of microbial preparations in plant-growing can be due to the correction of biological processes in agroecosystems and stimulates growth and development of plants. The efficiency of this process is dependent on biotic and abiotic factors, however their influence on introduction microorganisms in phytosphere is insufficiently studied. The article summarizes some results of recent studies, related to the impact of a number of environmental factors on physiological and biochemical activity of nitrogen-fixing bacteria Azotobacter vinelandii IMV B-7076 and phosphate-mobilizing strain Bacillus subtilis IMV B-7023 ­ components of Azogran, a complex bacterial preparation for plant growing. The dependence of the physiological and biochemical activity of these bacteria, including their antioxidant potential, on biotic and abiotic environmental agents was determined. The impact of a number of factors on chemotaxis, energy metabolism of these bacteria, their synthesis of substances of phenol nature, and other biologically active substances, which may influence the efficiency of using this preparation in plant growing, was studied. Azogran inhibits the spread of phytopathogens and some kinds of phytophages in agroecosystems, is capable of protecting plants from the oxidative stress and enhancing on 16­37 % their crop productivity.

[Physiological and biochemical activity of bacteria during germination of cucumber seeds and impact of ciliates Colpoda steinii on this process].

It is shown that the bacteria Bacillus subtilis B-7023 IMV produce indole-3-acetic acid and amino acids in the liquid medium Knoop. Processing cucumber seed suspension containing 10(7) cfu/ml as bacilli, and Azotobacter vinelandii IMV V-7076, resulted in a decrease in the length of the roots of plants. Reduction of bacterial load bacilli to 10(6) cfu/ml followed by reduction of indole-3-acetic acid in the medium, and to an increase in the length of roots, shoots and total plant mass. During the cultivation of Bacillus subtilis IMV V-7023 with ciliates Colpoda steinii reduced the amount of free forms of auxin in the medium to 5.5 times, and the related--to trace amounts. The content of histidine, phenylalanine, tyrosine, methionine and lysine significantly reduced.

[Bacillus subtilis and streptomycin resistant mutant growth in the medium with saponite].

The influence of dispersed saponite on growth activity of Bacillus subtilis IMV B-7023 and its streptomycin resistant mutant has been shown. The effectiveness of this process depends on the content of dispersed material and phosphate in the medium. It has been found that when B. subtilis is cultured in the medium containing 0.6 g/l PO4(3-) stimulation of bacteria growth is observed, but at a lower concentration (0.1 g/l PO4(3-)) there is a decline in the culture growth activity. At the same time streptomycin resistant mutant is shown to increase growth activity in the growth medium which contains up to 1.0 g/l saponite, regardless of the concentration of phosphate. It is shown that this effect is a consequence of uniformity of surface properties of streptomycin resistant strain of bacteria and similar parent strain at a concentration of 0.6 g/l PO4(3-).

[Interrelations of infusoria with Azotobacter and their influence on plants].

Symbiotic coexistence of infusoria Colpoda steinii with bacteria of Azotobacter genus has been investigated. It is shown that when infusoria are incubated during 3 days with the cells of A. vinelandii IMV D-7076 selected in the logarithmic phase of growth, the number of colpods increased 19 times, and with A. chrooccum 20--only 1.8 times. After 6 days of incubation with bacteria selected in the phase of stationary growth the number of infusoria increased with A. vinelandii 10 times, and with A. chrooccum 20 - 9.2 times. Treatment of seeds by the bacterial mix of A. vinelandii and C. stenii stimulates their germination, growth of roots and sprouts at early stages of plants development as compared with the use of cultures of monobacteria. It is evident that infusoria Colpoda steinii as well as the bacteria of Azotobacter genus secrete biologically active substances which accelerate growth and development of plants.

[Influence of bacteria of Bacillus genus on the causative agent of bacterial cancer of tomatoes].

It has been shown that bacteria of the genus Bacillus inhibited the development of infection caused by Clavibacter michiganensis subsp. michiganensis, in tomatoes. Pre-sowing seed treatment with suspensions of Bacillus subtilis IMV B-7023 and Bacillus pumilus 3 enhanced resistance of plants to bacterial disease of cancer, probably due to the synthesis of biologically active substances with antimicrobial properties by these bacteria. Of the two strains of bacillus, differing by antagonist properties to C. michiganensis subsp. michiganensis, a significant stimulating effect on the growth and development of tomatoes was provided by the strain B. subtilis IMV B-7023, which is part of the bacterial preparations for crop production.

[Relationship of bacteria of Bacillus genus with ciliate Colpoda steinii and their impact on germination of plant seeds].

Features of symbiotic coexistence of bacteria of the genus Bacillus with ciliates Colpoda steinii have been studied. In their mutual cultivation during 10 days the number of bacteria B. subtilis IMV V-7023 was reduced 4.4 times, B. pumilus 3 - 3.4 times, B. megaterium 12 - 2.5 times. In the mixed culture with B. pumilus 3 the number of the ciliates increased gradualluy while under availability of the other two bacilli strains the number of protozoan increased in the first two days, after that their amount decreased. Treatment of some plants seeds by suspension of B. subtilis IMV V-7023 with the protozoan increased their germination and stimulated the growth of plants at the early stages of development.

[Features of Bacillus subtilis IMB B-7023 and its streptomycin-resistant strain].

Features of phosphate-mobilizing bacteria Bacillus subtilis IMB B-7023 and its streptomycin-resistant strain were investigated. While cultivated in medium with glucose and glycerophosphate, the growth rate of the antibiotic-marked strain was approximately similar to this parameter for Bacillus subtilis IMB B-7023 but cell sizes were 1.3-fold less. Both strains significantly stimulated the germinating of plant seeds, attached to their roots, and insignificantly differed in antagonistic activity toward phytopathogens and quantitative content of cell fatty acids and phosphatase activity. Streptomycin-resistant strain may be used for monitoring of Bacillus subtilis introduced to agroecosystem.

[Chemotactic and adhesive properties of Azotobacter vinelandii and Bacillus subtilis].

The effects of some factors on the chemotaxis of Azotobacter vinelandii IMV V-7076 and Bacillus subtilis IMV V-7023 and on their adhesion to cucumber roots have been studied. Glucose chemotaxis and adhesion to roots reach peak values in pH ranges characteristic of each strain. These ranges are 7.0-8.0 for A. vinelandii IMV V-7076 and 6.0-7.0 for B. subtilis IMV V-7023. The adhesion values of each species decrease significantly in their mixed suspension. The interaction of each of the strains with the clay mineral montmorillonite improves their adhesion to cucumber roots. The clay mineral palygorskite improves the adhesion of A. vinelandii but reduces that of B. subtilis.

[Influence of titanium dioxide on growth of Azotobacter vinelandii IMV V-7076].

Adding highly dispersed titanium dioxide particles of the culture medium has a stimulatory effect on growth of Azotobacter vinelandii. The maximum effect was observed when using 5 g/l and 10 g/l concentrations of this component. Under these conditions the number of grown bacteria is several times more than in the control variants. It was shown that the stimulatory effect could not be the consequence of saccharose sorption on the surface of particles of the dispersed compound. Possibly, the contact interaction of bacterial cell with titanium dioxide causes an increase of cell wall permeability which leads to an increase of substrates transport to the cell.

[Growth peculiarities and properties of Bacillus subtilis IMV B-7023 cell surface in the medium with glycerophosphate].

It is established that, depending on the amount of the basic elements of carbon and phosphorus nutrition in the cultivation medium, Bacillus subtilis IMV B-7023 can use glycerophosphate as a source of carbon, carbon and phosphorus, or phosphorus. The found differences in bacterium physiology correlate with the change of cell surface properties.

[Production of biologically active substances of indol nature by bacteria of Azotobacter genus].

A stimulating effect of Azotobacter vinelandii IMB B-7076 bacteria on germination of seeds and formation of germs of different plants has been shown. One of the factors, which determines such phenomenon is the accumulation of biologically active substances in culture medium. The researched bacteria of Azotobacter genus accumulate indoleacetic acid (IAA) in the culture medium. Other substances of indol nature have been identified in the culture medium of these bacteria. It has been shown, using the computer's program PASS that these substances cannot take part in the regulation of plants growth. However 1H-indole-3carboxaldehyde can be characterized by antagonistic activity.

[Colonization of cucumber rhizosphere by phosphate-mobilizing bacteria of Bacillus genus].

An ability of phosphate-mobilizing bacteria, related to four species of Bacillus genus, to colonize the cucumber root zone has been investigated. It has been found that all the studied strains can adapt to the root zone of those plants colonizing its parts to different extent. Essential nonuniformity of the root surface populating with bacteria is noted. Microcolonies of these organisms are formed in some root zones. This peculiarity is probably caused both by the difference in the number and composition of exudates of some zones of the plant roots, and by peculiarities of trophic requirements of the strains of studied bacteria The paper is presented in Ukrainian.

[Adhesion of Azotobacter vinelandii IMV V-7076 and Bacillus subtilis IMV V-7023 on different surfaces].

The dependence of Azotobacter vinelandii IMV V-7076 and Bacillus subtilis IMV V-7023 adhesion on some parameters of dispersion media (pH, Ca 2+ ions presence) has been investigated. It has been determined that a decrease of bacteria negative charge determines an increase of the degree of their attachment to abiotic surface (glass) that corresponds to physicochemical regularities of the given process. The adhesion of bacteria on the biotic surface (cucumber roots) is not subordinated to generally accepted ideas, according to which the electrostatic repulsion between the interacting objects is one of factors that determines the adhesion effectiveness.

[The effect of Azotobacter vinelandii on plant seed germination and adhesion of these bacteria to cucumber roots].

Bacterization of seeds of several plant species with Azotobacter vinelandii suspension stimulates their germination to different degrees. This demonstrates that seeds of different species display different sensitivity to the biologically active substances accumulating in the culture liquid of these bacteria. The adhesion patterns of these bacteria to cucumber roots were studied. The maximal number of cells adhered to the root surface at the phase of culture logarithmic growth (24 h), when they were motile. The loss of motility in the stationary growth phase (72 h) decreased the number of cells adhered to roots by 80%.

[Electrical properties and interaction with silicon dioxide particles of Bacillus subtilis cells].

It was shown that, depending on the quantity of phosphate in cultivation media, the surface layer of the Bacillus subtilis cell wall can mainly consist of either teichoic or teichuronic acids. It was found that the addition of silicon dioxide particles to the bacterial suspension induces an increase in the negative charge of the cell. This cell response to contact interaction with solid particles is observed in bacteria whose surface components are teichoic acids.

[Effect of cultivation conditions of Bacillus subtilis IMV B-7023 on surface properties of cells].

It has been established that the cells of Bacillus subtilis IMV B-7023 grown on the medium where peptone or calcium glycerophosphate served as the only source of carbon and energy have similar acid type of the surface and are characterized by a high negative charge even at low values of pH of the dispersion medium. This may be determined by the presence of phosphate groups, teichoic acids being their carriers in Gram-positive bacteria. Glucose addition to peptone or glycerophosphate leads to the change of the bacteria surface type, i.e., at low values of pH the cells have total positive charge, that allows to suppose availability of protein nature components in the surface layers of the cell wall. Bacteria grown in these conditions are also characterized by the higher degree of adhesion to inert carrier (glass).

[Soil microflora over the closed Donbas mines].

Composition of soil air and microflora in different soil horizons (to 30 cm depth) over some closed Donbas coal mines has been studied. The intensive methane leakages have been found in some soil zones over the closed coal mines. This results in formation of explosive and inflammable gas mixtures. Methane content in soil gas mixtures could vary from trace amounts to 34 %. The essential decrease of oxygen (to 3-4%) and increasing (up to 5 %) of CO2 concentrations that evidences for active microbiological processes in such soils is marked in the latter case. Methanotrophic bacteria involving methane into biogenic cycle are widespread (up to 106 cells per 1 g) in methane-containing soils over the closed coal mines. Microorganisms of different physiological groups in the community with methanotrophic bacteria were found in the given technogenic econiche.

[Interaction of some Pseudomonas genus representatives with high-dispersed silicon dioxide particles].

The effect of increase of a negative charge in the cell during contact interaction with silicon dioxide particles similar to those previously obtained for methanotrophic bacteria was observed in pseudomonads. The microelectrophoretic method application has allowed to find a capsule and consists of uncharged components in Pseudomonas batumici bacterial cells; the capsule thickness was determined by conditions of microorganisms cultivation. The effect of increase of a negative charge took place for the cells grown on the Kozer medium where they formed a capsule of smaller dimensions. It is supposed that the sorption of silicon dioxide particles on the bacterial surface initiates the conformational changes of porins. As a result, the quantity of the charged groups increases and thickness of the surface layer in which these groups are located also augments.