[Sporulation of Bacillus subtilis in Binary Cultures with Ultramicrobacteria].

The effect of ultramicrobacterial epibionts of the genera Kaistia (strain NF1), Chryseobacterium (strain NF4), and Stenotrophomonas (strain FM3) on the process of sporulation of Bacillus subtilis ATCC 6633 was studied. The investigated strains of ultramicrobacteria (UMB) were found to inhibit the sporulation process of B. subtilis ATCC 6633 in binary mixed cultures, exhibiting a 3-day delay of the onset of sporulation compared to the control one, an extended period of the prospore maturation, formation of the fraction of immature spores, and development of ultrastructural defects in many endospores.

[Effect of cold plasma on the E. coli cell wall and plasma membrane].

The effect of cold plasma on E. coli cells was studied. It was shown that the treatment of E.

[Corrosive activity of natural microbial associations at various conditions of cultivation].

Influence of microbial associations isolated from different ecological niches on corrosion of mild steel was changed depending on composition of medium and aeration regime. Both decrease and increase in corrosion losses were observed, which indicated that the subdivision of microorganisms into destructors and passivators of corrosion is merely conventional.

[Electron microscopic detection and in situ characterization of bacterial nanoforms in extreme biotopes].

The morphology, ultrastructure, and quantity of bacterial nanoforms were studied in extreme biotopes: East Siberia permafrost soil (1-3 Ma old), petroleum-containing slimes (35 years old), and biofilms from subsurface oil pipelines. The morphology and ultrastructure of microbial cells in natural biotopes in situ were investigated by high-resolution transmission electron microscopy and various methods of sample preparation: ultrathin sectioning, cell replicas, and cryofractography. It was shown that the biotopes under study contained high numbers of bacterial nanoforms (29-43% of the total number of microorganisms) that could be assigned to ultramicrobacteria due to their size (diameter of < or =0.

Evidence that membrane insertion of the cytosolic domain of Bcl-xL is governed by an electrostatic mechanism.

Signals from different cellular networks are integrated at the mitochondria in the regulation of apoptosis. This integration is controlled by the Bcl-2 proteins, many of which change localization from the cytosol to the mitochondrial outer membrane in this regulation. For Bcl-xL, this change in localization reflects the ability to undergo a conformational change from a solution to integral membrane conformation.

[Corrosion of pipe steel samples and conjugated conversion of sulfur compounds by thiobacteria Halothiobacillus neapolitanus DSM 15147].

The kinetics of conversion of sulfur compounds by Halothiobacillus neapolitanus DSM 15147 bacteria was studied in the presence of steel samples. It was shown that the presence of steel altered the known pathway of sulfur compound oxidation by thiobacteria. Production of atomic hydrogen via the interaction between biogenic sulfuric acid and steel enhanced secondary production of intermediates and decreased the content of sulfate produced previously.

[Rapid assay for the assessment of a potential of chemical biocides to microbial destructors of industrial materials].

A colorimetric rapid assay for estimating the biocide potential of various chemicals towards metal biocorrosive and petroleum product degrading microbes was developed based on the reducing potential of live microbial cell. A water-soluble organic redox indicator, blue in the oxidized form and pink in the reduced form, was used as an indicator of the reducing potential of microbial cells. Once added to a suspension of vital microbial cells, it was reduced and changed in color.

[Direct quantitative method for evaluating the effect of biocides on Pseudomonas fluorescens in different culture media].

A method for quantitative evaluation of the effects of biocides is presented. The method was tested in experiments with Pseudomonas fluorescens grown on various agar nutrient media. The effective concentrations of biocides that decreased the maximum specific rate of the colony biomass growth (mu'm) were called S (suppressing) concentrations, and concentrations that decreased the number of colony-forming units (CFU) were taken as L (sublethal) concentrations.

[Increase in the ecological danger upon the use of biocides for fighting corrosion induced by microorganisms].

Five synergistic combinations of biocides were found, among which the combination of kathon + copper sulfate was the most efficient against Serratia marcescens. Depending on the ratio of these biocides, the synergistic effect of this pair allowed 4-20-fold decreases in the effective concentrations. Combinations of biocides with salts (carbonates and phosphates) that facilitate passivation of steel were found, which considerably decreased the corrosion losses of mild steel in comparison to isolated treatment with biocides or salts.

[Chemical-microbiological diagnosis of stress-corrosive damage to pipelines]].

Samples of soil, ground, electrolyte, corrosion products, and protective coating were taken after excavating pipelines. The depth of stress corrosion cracks of the pipe steel was mostly related to the numbers of sulfate-reducing and denitrifying bacteria. In certain types of soil, damage correlated with the number of acid-producing microorganisms and aerobic chemoorganotrophs (saprophytes).

[Creation and use of a liquid substance based on association of petroleum-oxidizing bacteria].

An association of four bacterial strains with high oil-oxidizing and bioemulsifying activities, psychrophilicity, resistance to chemical pollutants, and lack of pathogenicity was selected from a collection of natural oil-oxidizing microorganisms. A new liquid preparation containing stabilizers and preservatives that maintain the cell viability and oil-oxidizing activity during long-term storage was developed. A field experiment in oil-polluted sod-podzol and clay sand soils demonstrated that this preparation accelerated the biodegradation of oil and its individual fractions, especially in the presence of mineral and organic fertilizers.

[Development and testing of "Ekosorb" biosorbent based on association of petroleum-oxidizing bacteria for purifying petroleum-polluted soils].

A biosorbent containing an association of oil-oxidizing bacteria as a main constituent was developed, in which Lessorb, a product of moss and wood thermal processing, was used as a carrier. Xeroprotectors preserving the cell viability and oil-oxidizing activity in the biosorbent on drying and after long-term storage were selected. The use of this biosorbent for cleaning oil-polluted sod-podzol soils showed a two-threefold cleanup rate acceleration at different pollution levels (8 and 24 l/m2), especially in the presence of a nitrogen-phosphate fertilizer.

[Study of the integral toxicity of aqueous media, polluted by petroleum and petroleum products using bacterial tests].

A biotest kit was used to assess the integral toxicity level of aquatic medium contamination with petroleum and petroleum-based products. The integral toxicity dynamics was also monitored during biodegradation of petroleum and petroleum-based products by an association of petroleum-degrading strains including Acinetobacter sp., Mycobacterium flavescens, and Rhodococcus sp.

[Plant biotests of soil and water, polluted with petroleum and petroleum products].

Reactiona of higher plants (mustard, oat, rye, salad, dill and barley) and microalgae (Euglena gracilis) on the contamination of soil and water with petroleum and oil products was studied. The germination of seeds was analyzed. The length of sprouts, dry biomass and length of plant roots, as well as the optical density of micro-algal broth culture were determined.

[Effect of space flight conditions on properties of hydrocarbon-oxidizing bacteria].

Results of experiments on the Mir space station (EO-25 and EO-26) demonstrated that the conditions of orbital flight, primarily the cosmic radiation, was a mutagenic factor affecting both the genotype and phenotype of an oil-oxidizing bacterial strain, Mycobacterium flavescens EX-91. The emerging mutants differed from original culture by the rate of colony growth and the ability to ferment certain carbohydrates or synthesize beta-galactosidase. Changes in the rate of utilization of raw oil and individual hydrocarbon types (constituting model mixtures) suggest that cosmic radiation may serve as a means of obtaining mutant clones of microorganisms with new properties.

[Initial stages of steel biocorrosion].

Initial stages of corrosion of mild steel induced by Klebsiela rhinoscleromatis BO2 were studied in various media. The effect of the microorganism was detected 8-10 h after inoculation. The number of viable cells were virtually unchanged within one month in all media, but the corrosive activity of the strain decreased.

[Microbiological degradation of asymmetrical dimethylhydrazine--a toxic component of rocket fuel].

A possibility of microbiological cleaning of water and soil polluted with asymmetric dimethylhydrazine (ADMH), a highly toxic rocket fuel ingredient (RFI), was studied. Several isolates (bacteria, yeast, and micromycetes) capable of utilizing ADMH as the only source of nitrogen, carbon, and energy were isolated from RFI-polluted tundra soil. Acceleration of RFI biodegradation was achieved using a biosorbent that involved cells of the degrader strain immobilized on granulated activated carbon.

[Simplified model of increase in colony diameter during growth of unicellular microorganisms and its use in evaluating the effect of biocides on microbial cells].

A simplified model of increase in colony diameter is proposed. The model uses the size of single cells and several measurements of colony diameter during linear growth for calculating with good approximation the growth curve for the culture from the moment of inoculation. The parameter mu(m)', which is approximately 10% lower than the maximum specific growth rate of the colony biomass, could be also calculated.

[Effect of water pollution by oil and oil products on barrier functions of bacterial cell cytoplasmic membranes].

The effects of oil, diesel fuel, and kerosene on the electroorientational spectra and osmo-optical characteristics of bacterial cells were studied. Electroorientational spectra were found to be affected over the entire frequency range studied; changes in low-frequency (< 100 kHz) electroorientation were related to alterations in the cell surface, and those in high-frequency electroorientation, to the impairment of the barrier function of the plasma membrane. The membranotropic activity of petroleum products was also demonstrated by the osmo-optical method.

[Various biochemical properties of Salmonella strains isolated from animal food products].

Studied were a total of 488 Salmonella strains isolated from food products and washings from productional surfaces for the presence of variants, with the use of tests of producing gas from glucose and hydrogen sulfide and the coincidence of the two properties. It was found that 7 species only had biochemical variants. Most frequent were the variants with S.

[Presence of salmonellae and coliform bacteria in ground meat and the sources of its contamination].

Studied were a total of 14,944 samples of minced meat for the presence of Salmonellae and 608 samples for establishing the coli-titer. Examined were also bacteriologically 5651 washing samples from the workers' hands, the machines, equipment and stock implements in the shops for the production of minced meat prior to starting work as well as 3721 washing samples from the same for the presence of coliforms. It was found that 1.

Transport of amino acids and calcium in the fungus, Phytophthora infestans.

Amino acid transport in the cells of calcium-dependent fungus Phytophthora infestans has been largely studied with respect to phenylalanine. It is defined as an active process in a number of characteristics. The reasons for that are as follows: 1) accumulation of amino acids is inhibited by carbodiimide and ruthenium red, which suggests the participation of an intermediate; 2) the transport is energy-dependent, since it is inhibited by potassium cyanide, sodium azide and 2,4-dinitrophenol.

Energy-dependent transport of manganese into yeast cells and distribution of accumulated ions.

Manganese transport into yeast cells is energy-dependent. It is dependent on endogenous sources of energy and is inhibited by olygomycin (12.5-25 microgramg/ml), 2,4-dinitrophenol (1 mM), 2-deoxyglucose (1-50 mM) and sodium azide (1-10 mM), but is stimulated by cyanide and glucose.

Isolation and properties of an arginine-binding protein from Saccharomyces cerevisiae.

Transfer of exponentially growing cells of Saccharomyces cerevisiae epsilon 1278 b to a fresh medium (or simply to distilled water) resulted in the loss of ability to transport arginine (and lysine), accompanied by the release of several proteins from the membrane surface or periplasmic space. Fractionation by ultrafiltration, Sephadex G-50 chromatography and freeze-drying yielded a homogeneous protein (55 mg per 100 g dry weight of cells) with specific binding ability for L-arginine (Kd = 3.8 X 10(-1) M) and L-lysine (Ki = 4.