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It was stated that spaceflight factors (SFF) affect the chromosomal DNA interchange during Streptomyces crossing. Cross polarity and primary input of a parent chromosome fragment in recombinant generation imply a more lasting cells contact in microgravity and a broader horizontal transport of genetic material. SFF had no effect on recombination frequency and mutation in a model of parental auxotrophic markers reversion to prototrophism. It was demonstrated that SFF boosted the fC31 phage exit from S. lividans 66 (fC31) and did not influence phage induction in S. coelicolor A3(2) (fC31). SFF inhibited synthesis of antiobiotic actinorhodin in lisogenic S. coelicolor A3(2), and tylosin and desmicosin in S. fradiae. Survivability of electrogenic bacteria Shewanella oneidensis MR-1 in space flight was higher compared with the synchronous control experiment. The reduction activity of S. oneidensis MR-1 as an indicator of electron generation effectiveness was identical in flight and laboratory samples.

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Dysbiotic shifts in intestinal and pharyngeal microflora were studied in 22 normal volunteers in 9-, 14-, 105- and 520-d chamber experiments simulating some of the spaceflight factors. Two preparations were administered to prevent pharyngeal and intestinal dysbiosis: oral dry probiotic based on indigenous intestinal Enterococci and topical collagen-immobilized Lactobacterin based on indigenous intestinal Lactobacilli. Topical autopmrobiotic lactobacterin reduced the growth of opportunistic pathogens in the throat during the experiments. Oral autoprobiotic based on Enterococci reduced the content of intestinal opportunistic pathogens, supporting the high level of protecting microflora. Most of autostrains are free from pathogenicity factors, nevertheless, implementation of genetic testing of indigenous strains are reasonable.

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The in silico analysis of 36 sequenced genomes of bacteria of the Bifidobacterium genus determined the presence of 19 genes of toxin-antitoxin (TA) systems that belong to the MazEF and RelBE families, including five mazF and two relE genes that encode toxins and 12 relB genes that encode antitoxins. A high level ofgene (at the level of nucleotide changes) and genomic (presence or absence of genes in distinct genomes) polymorphism in the investigated genes was revealed. The highest level of polymorphism was observed in strains of the Bifidobacterium longum species, primarily in relB1-10 genes. Gene and genomic polymorphism might be used to identify the strain of B. longum species. PCR analysis ofgenomic DNA of 30 bifidobacteria strains belonging to the three species, B. longum, B. adolscentis, and B. bifidum, isolated from the intestinal microbiota of astronauts demonstrated the presence of mazF and relB genes. The observed polymorphism of TA genes indicates the presence of differences in bifidobacteria strains isolated from the intestinal microbiota of astronauts before and after space flight and the control group.

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The vegetable cultivation technology developed in view of long-term autonomous missions is based on root nutrition provided by fiber artificial soils (AS) containing ion-exchange resins. Useful life of ASs is limited by two factors which are nutrients depletion in ion-exchanger and clogging of the AS threshold space by roots remnants. Purpose of the investigation is to try out hydrolysis and ensuing microbial decomposition of roots remnants as a way to extend the resource of used fiber ionite AS. This principle of doing away with the roots remnants recovers almost completely the maximal water-absorbing capacity of AS BIONA-V3 so that it can be used again for crops cultivation.

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Purpose of the work was designing and prototyping of microbial fuel cells (MFC) and comparative evaluation of the electrogenic activity of wastewater autochthonous microorganisms as well as bacterial monocultures. Objects were model electrogenic strain Shewanella oneidensis MR-1, and an Ochrobactrum sp. strain isolated from the active anode biofilm of MFC composed as an electricity generating system. The study employed the methods typically used for aerobic and anaerobic strains, current measurement, identification of new electrogenic strains in microbial association of wastewater sludge and species definition by rRNA 16-S. As a result, two MFCs prototypes were tried out. Besides, it was shown that electrogenic activity of S. oneidensis MR-1 and Ochrobactrum sp. monocultures is similar but differs from that of the microbial association of the anode biofilm.

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Automated digital image microscopy was used to evaluate skin microbial populations in 14- and 105-day isolation experiments within the Mars-500 project.

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Microbial contamination of integument was evaluated in test-subjects volunteered for 7-day immersion with the purpose to evaluate a technology of automated analysis of human microbiocinosis. Integument microflora was investigated in the baseline data collection period and on day-7 of immersion with the help of the standard bacteriological method and using a prototyped automated analyzer. The investigation showed the possibilities of the automated analyzer to provide operating data about human microflora.

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Two hundred and two intestinal lactobacill strains were obtained and studied in a 30-d experiment with chambered human subjects. Species composition of intestinal lactobacilli varied in the course of the experiment. Species of lactobacilli persisting in organism in the period of isolation were identified.

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The sanitary-hygienic well-being of 6 volunteers for the 105-d chamber experiment simulating some of the spaceflight factors was evaluated. To evaluate the pertinent means and methods, clinical, hygienic and microbiological investigations were employed, and volunteers' subjective opinions of personal hygiene items and associated procedures were analyzed Based on the examination of integument and oral cavity, entries in the questionnaires concerning subjective sensations, opinions and objective data, all volunteers were invariably in good state. Level of the skin total microbial contamination was found to depend on volunteers' diligence to fulfill the hygienic routine.

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Presented are the results of studying bacterial methane generation and oxidation in the body of solid domestic wastes dump and intensity of gas release into atmosphere. The investigation revealed active microbial degradation of organic wastes with a distinct biogeochemical zoning. Quantitative and qualitative composition of micro-organisms depends on the depth of horizon. Disintegration of organic components of warehoused foods by various microorganisms occurs with production of volatile and gaseous compounds (carbonic acid, methane and others). Anaerobic conditions set the scene for active production of biogas, major components of which are methane and CO2. The final process in the sequence of organics transformations within the body of solid domestic wastes dump is predominant production of CH4 and CO2 in the ratio of approximately 60 and 40%, respectively, and trace quantities of other volatile compounds. Active bacterial methane oxidation is evidenced by the 13C isotope increase in methane and decrease in carbonic acid. The developed model of animal and plant wastes management demonstrated efficiency of the system using frozen-dried preparations of microbial associations and its practicability in municipal economy.

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One of formidable issues of experiments with animals in space flight is water supply. For Mongolian gerbils (Meriones unguiculatus), classed as cricetid rodents, water in chow is enough. These animals are a new object for space biology. Our purpose was to compose a full-value formula and design a chow making and long-term storage technology to provide Mongolian gerbils for in microgravity. The chow is required to have a 28-d shelf life. To assess the chow suitability on autonomous space fight, the gerbils we house in a cage with the geometry reproducing the current design of the future space animal module. The assessment was performed with adult male gerbils weighing 50.5 +/- 3.4 g on the average. The animals ate up 40.1 +/- 3.9%, i.e. less than 50% of the feed all through the period of experiment. However, by the end of the experiment the body mass and exterior remained essentially unchanged In was concluded that the chow formula can be prescribed to Mongolian gerbils housed in self-contained modules.

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Daily dynamics of pharyngeal microflora was evaluated in the absence of preventive treatment and using a local lactate-producing probiotic preparation during 24 hour-long simulated microgravity. The study showed that the short-term application of the local lactate-producing probiotic (four times daily) significantly reduced titers of opportunistic pathogenic microflora and increased the amount of symbionts in the pharynx.

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Development of acute hypoxic hypoxia in consequence of fire in various pressurized modules was studied. The investigation was aimed to look into the effects of inert argon and dramatic oxygen reduction in gaseous environment on animals (Wistar rats, mice c57bl/6, balb/c and f1cbaxbalb/c hybrids, Japanese quail embryos) and microorganism (Escherichia coli strains k-12 jf 238 and k-12 jm 83). Also, inflammability of some widely used materials was assessed in order to provide inputs to developers of fire-safe gaseous mixtures for pressurized habitats. It was shown that argon is favorable to survivability of animals and to maintenance of a high level of oxygen consumption. Gaseous mixtures with oxygen content less than 15 volume % suppressed burning of selected materials. Results of the investigation offer possibilities for designing new hypoxic fire-safe gas mixtures that will provide adequate human performance and ensure survival in extreme situations.

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Dysbiotic shifts in intestinal and integumentary microflora were studied in 10 test-subjectes during 7-day "dry" immersion. Essentially every test-subject reduced significantly fecal lactoflora and developed dysbiotic shifts in the microbial landscape of various types of integument. Pharyngeal microflora was analyzed in 22 normal volunteers for 7-day "dry" immersion. Two probiotic preparations were administered to prevent pharyngeal dysbiosis: peroral dry lactobacterin and topical collagen-immobilized lactobacterin. The peroral probiotic stimulated growth of pharyngeal opportunistic pathogens preventing translocations of the intestinal microflora. The topical probiotic, on the opposite, reduced the content of opportunistic pathogens in the throat; however, it provoked gastrointestinal dysbiosis. It appears that the most effective prophylaxis of pharyngeal dysbiosis can be reached by prescription of both topical and peroral probiotics.

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The review has been undertaken within project Mars-500 supported by the Russian Academy of Sciences and aimed to make choice of a method and associated device for effective decontamination and warming potable water for humans during long confinement and isolation. Analysis of the literary data and patent specifications of chemical, physical and hybrid methods of water decontamination and warming guided the choice of energy of ultrahigh frequencies (UHF). Also, a waveguide-coaxial UHF-device implementing this method was proposed. Ease of the UHF energy transformation to heat, reliability, friendliness and impart attractiveness to the method in the eye of developers of long-operating physical-chemical life support systems.

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We studied pharyngeal microflora in 22 healthy volunteers after 7-day dry immersion. For prophylactic pharyngeal dysbiosis, we used two probiotic drugs: oral -- "lactobacterin dry" and local --"lactobacterin immobilized on collagen". Administration of oral probiotic was accompanied with growth of pharyngeal opportunistic microflora preventing translocation of intestinal microflora. Local probiotic, on the contrary, decreased opportunistic microflora in the pharynx, but was associated with gastrointestinal dysbiosis. It is evident that combined use of topic and oral probiotic provides maximal effective prophylaxis of pharyngeal dysbiosis.

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An automated hematological analyzer, prototype of a quick microbiological diagnostics system, was tested positively for the ability to differentiate microbial cells (six test-strains with different morphological and tinctorial properties) by geometry and dye intensity.

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The purpose was to study morphological specifics of microbial colonies cultivated in argon-containing gas medium. Investigated were computerized images of the colonies of museum strains Escherichia coil K-12. It was found that combination of elevated argon pressure (1 ata) and nitrogen pressure (1.8 ata) increased the maximal density of microbial colonies and decreased the colony size as compared with cultivation in argon only.

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Subject of the study was frequency of transfer of bacterial plasmids determining the antibiotic resistance (R-plasmid) in argon-containing gas mixtures. Investigated were reference strains of Escherichia coli K-12. Conjugation took place during incubation in pAr/pN2/pO2, ata (1 ata = 10(5) kPa): No. 1 - 0.0/0.8/0.2 (air control); No. 2 - 1.0/0.8/0/2; No. 3 - 0.0/1.8/0.2; No. 4 - 1.0/1.8/0.2. E.coli conjugation was found inhibited after 24 hrs. of incubation with pAr elevated to 1 ata, whereas elevated partial pressure of argon (1 ata) and nitrogen (1.8 ata) brought transfer frequency down to the minimum.

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