[Componential composition of chlororganic pollutants and state of soil microbial cenosis in soil from burial place of waste].

The authors have identified 25 chemical pollutants in soil and 12--in the chemical composition of technical waste from chemical production. Broad spectrum of pollutants and their degradation products (26 chemical components) have been also detected outside the proving ground (2 km). This fact evidences for active spreading of chlororganic toxins into neighboring areas. Abnormality in functional activity and functions of soil microbial cenosis of the proving ground has been established: the number of oligonitrophillus, ammoniating, phosphate-mobilizing, amylolytic and pedotrophic microorganisms. Abnormalities of functional activity were manifested in the 1.6-1.9-fold augmentation of basal respiration and deterioration of substrate-induced respiration in comparison with control variant.

[Toxic and mutagenic influence of hexachlorocyclohexane and its microbial destruction products on soil microbial cenosis].

Microbial strains Pseudomonas putida 9, Stenotrophomonas maltophilia IMV B-7288 destructed hexachlorcyclohexane (HCH) isomers complex by 31.1-76.6 and 30.7-73.2%. respectively, in comparison with given level. HCH and its destruction intermediates had toxic and mutagenic influence on soil microbial associations decreasing their survival to 6.9-21.7%. The investigated destruction products and intermediates obtained by Pseudomonas putida 9, Stenotrophomonas maltophilia IMV B-7288 have demonstrated weak mutagenic properties. The use of cultures-destructors opens the prospects for application of the mentioned strains as the components of microbial biopreparations for remediation of polluted soils. The use of soil microbial cenosis as the test-system for ecotoxicological assessment permitted to obtain more detailed pattern of toxic and mutagenic properties of HCH and products of its destruction.

[Physiological properties and taxonomic position of soil microorganisms-destructors of hexachlorcyclohexane].

Eleven (11) microbial strains capable to decompose insecticide hexachlorcyclohexane (HCH) have been isolated from microbial association resistant to chloro-organic pesticides. On the basis of investigation of morphological, cultural, physiological, biochemical characteristics and results of sequence of gene 16S rRNA it has been established, that the best strain-destructors N 3 and N 9 belong to Pseudomonas putida species, and strain N 6 belongs to Stenotrophomonas maltophilia species.

[Study of mutagenic activity of hexachlorocyclohexane and products of its microbial degradation].

Mutagenic activity of hexachlorcyclohexane (HCH) was investigated. As is known, gamma-isomer of HCH has insecticidal properties. The strains of microorganisms of genera Pseudomonas, Stenotrophomonas, Bacillus decomposing HCH into 46.3-86.7% from initial quantity have been selected. Microbial HCH destruction by investigated strains made changes of pesticide genetic activity: in most cases in condition of intermediate action the quantity of mutations S. typhimurium TA 100 and S. typhimurium TA 98 have decreased 1.2-1.5 times in comparison with initial substance. In a single case after HCH transformation by strain P. putida 1 the intermediates have increased the mutation frequency 1.9 times. The obtained results are necessary for selection of the most promising strains-decomposers as a basis of biopreparations for remediation of HCH polluted soils.

[Protective properties of avermectine complex and plant growth regulators].

Antimutagen properties of avermectine complex of Avercom synthesized by Streptomyces avermitilis UCM Ac-2161, and growth regulators of plants (GRP) of bioagrostim-extra, ivin and emistim-C have been revealed in experiments with test-cultures of Salmonella typhimurium TA 100, TA 98. Avercom and plant growth regulators neutralize by toxication 27-48% and mutagen action of pesticides on soil microbial associations by 19.0-30.0%.

[Effect of heavy metals on the growth of soil streptomyces]. / Vplyv vazhkykh metaliv na rist gruntovykh streptomitsetiv.

The effect of heavy metals on the streptomycete pure cultures under solid and liquid nutrient media has been studied. There were revealed streptomycete forms sensitive and resistant to heavy metals. Streptomyces versipellis strain 1, S. griseoalbus strain 6, and S. viridogenes strain 570 belong to the first group. The increase of metal content in the agarized medium caused the decrease of the number and dimension of colonies, capacity for sporulation and loss of aerial mycelium, soluble pigment, and, at last, death. These cultures may be used as indicators of the soil heavy metal pollution in the future. The resistant streptomycete forms had good growth under experimental conditions and could accumulate the metals in the liquid media: S. flavovirens, strain 12,--about 230 micrograms of copper ions, S. albaduncus, strain 279,--209 micrograms of cadmium ions and S. alboviridis, strain 141-653 micrograms of lead ions per 1 g of dry mycelium. It is supposed that these streptomycetes, when assimilating the above metals in amounts required for life about can exclude them from the circulation and can decrease the metal negative influence on plants.

Streptomycete complexes of "Evolution Canyon" soils (Mount Carmel, Natural Preserve, Israel).

It had been studied the quantitative and qualitative structure of the soil Streptomyces complexes at three ecotopes of "Evolution Canyon" (Israel) for the first time. Numbers of streptomycetes changed from 3'000 to 15'000 CFU per 1 g of dry soil depending on edaphic and microclimatic conditions. Eighty-eight species and subspecies were found as a whole. Synecological analysis demonstrated the high difference between the soil Streptomyces complexes of various Canyon' ecotopes, opposite stations and stations across the Canyon.

[Prospects for storing streptomycetes in atmospheres of various gases]. / K voprosu o vozmozhnosti khraneniia streptomitsetov v atmosfere razlichnykh gazov.

The possibility of Streptomyces cultures preservation in the atmosphere of argon, nitrogen, carbon dioxide and free air (the latter as a control) has been first studied. The possibility of short-term (4-6 months) preservation of Streptomyces cultures in the atmosphere of argon and nitrogen has been demonstrated. Some cultures could be preserved in the argon and nitrogen atmosphere for 26 years.

Alternation of exo- and endotrophy during the mitotic cycle of the yeast cells.

The utilization of the intracellular and extracellular sources of carbon and energy during the mitotic cycle of yeasts Saccharomyces cerevisiae, Kluyveromyces marxianus, Candida boidinii, Candida tropicalis has been studied. Increase in the consumption rate of carbon and energy sources and in the exogenous respiration rate at G1- and G2-phases of the mitotic cycle is shown. The rate of the endogenous respiration of the cells at these phases decreased. The hypothesis has been proposed that during the mitotic cycle of the yeast cell the regular alternation of exotrophy (the utilization of the extracellular carbon and energy sources by a cell) and endotrophy (the process of the utilization of the intracellular carbon and energy sources by a cell) occurs. It is possible to reveal the exotrophic cells by the cytological method which is based on the calculation of dead cells after incubation of the yeast suspension in amyl alcohol solution. This method has revealed that exotrophic and endotrophic processes do not predominate one over another but alternate at the mitotic cycle. Exotrophy and endotrophy are phase-specific processes. The G1- and G2-phases are exotrophic processes, phases S and M are endotrophic ones.

[Effect of cultivation conditions on the age structure of a yeast population]. / Vliianie uslovii kul'tivirovaniia na vozrastnuiu strukturu drozhzhevoi populiatsii.

The work was aimed at studying the effect exerted by mineral components of the medium and a carbon source limiting the growth of Candida boidinii and Saccharomyces cerevisiae as well as by the dilution rate in the course of chemostat cultivation and by the temperature of growth on the age structure of a population, i.e. on the proportion of cells at different phases of the cell cycle. Nitrogen, phosphorus and magnesium deficiency delayed the growth of cells in the G1 phase and, if the growth rate was low, at the end of budding. The rise of the growth rate increased the proportion of budding cells. A temperature drop below 23 degrees C delayed the separation of the daughter and mother cells.