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The Antarctic region has significant potential to study the biodiversity of microorganisms and to search for bacterial producers of glycolytic and proteolytic enzymes with new properties. The aim was to study the extracellular glycosidase and proteolytic activity of four bacteria strains isolated from black lichens of the cliffs of Galindez Island in the Antarctic. Methods. Cultures of bacteria were grown in submerged conditions at a temperature of 15 and 26oC for 48 h. The synthetic and natural substrates such as p-nitrophenyl-glycosides, soluble starch, gelatin, casein and Elastin-Congo red were used to study the enzymatic activity of bacteria. Results. All studied strains showed α-fucosidase activity. Microbacterium foliorum, Sporosarcina aquimarina and Rothia sp. exhibited α-, β-xylosidase, β-glucosidase or β-N-acetylglucosaminidase activity in different ratios. That may indicate the presence of the enzymatic complex of hydrolysis of lichenan and xylan, which are part of polysaccharides of plants and lichens. P. fluorescens and M. foliorum also showed gelatinase activity. The enzymatic activity of bacteria was noted to be higher in the case of cultivating at 15oC compared to 26oC. The α-xylosidase of M. foliorum was optimally active at pH 6.0 and 35oC, the α-xylosidase of Rothia sp. – at pH 6.5 and 35oC. High level of stability was shown for these enzymes in the pH range from 4.0 to 7.0 and temperature from 15 to 35оС during 24 h. Conclusions. Antarctic lichens can be a source of bacterial producers of polysaccharide degrading enzymes with new properties and low temperature optimum. The Antarctic cold environment provides the great opportunities to study the adaptive mechanisms of microorganisms and their enzymatic systems in order to develop new biotechnologies.

UV irradiation is known to cause harmful effects on microorganisms. As the result, microorganisms have developed protection against exposure to harmful UV irradiation. We suggested that resistance to UV might be specific characteristic of certain genera of microorganisms. So, the aim of the work is to assess whether there is a correlation between UV resistance and the taxonomic position of microorganisms or is it the adaptation of cells to extreme conditions. There were studied 67 strains from extreme ecosystems (phytocenoses and оrnithogenic soil of the Antarctic, hypersaline ecosystems of the Crimea and the Dead Sea, the lake Baikal). Sequence of 16S rRNA genes, phylogenetic analysis and UV resistance were performed according to standard procedures. Phylogenetic analysis revealed live representatives of the following genera: Pseudomonas, Serratia, Rheinheimera, Aeromonas, Buttiauxella, Brevundimonas, Sphingomonas, Sphingopyxis, Dermacoccus, Frondihabitans, Microbacterium, Rhodococcus, Janthinobacterium, Arthrobacter, Micrococcus, Kocuria, Sphingobacterium, Flavobacterium, Chryseobacterium, Bacillus, Staphylococcus, Paenibacillus, Sporosarcina. Gram-positive bacteria were significantly more resistant to UV irradiation (LD99.99 750–1400 J/m2). Gram-negative had lower resistance (LD99.99 35–150 J/m2). Most pigmented strains were more resistant to UV than non-pigmented ones. According to the values of lethal doses of UV irradiation we suggest that investigated microorganisms have effective mechanisms to repair DNA damages. Resistance of microorganisms to UV, as a rule, was not related to the ecological features of their habitat. Thus, there is a correlation between the resistance of microorganisms to UV irradiation and their taxonomic position, which allows to consider UV resistance as a diagnostic feature at the genus level.

The constant increase in the amount of food waste accumulating in landfills and discharged into the water reservoirs causes environment pollution and threatens human health. Solid and liquid food wastes include fruit, vegetable, and meat residues, alcohol bard, and sewage from various food enterprises. These products contain high concentrations of biodegradable organic compounds and represent an inexpensive and renewable substrate for the hydrogen fermentation. The goal of the work was to study the efficiency of hydrogen obtaining and decomposition of solid and liquid food waste via fermentation by granular microbial preparation (GMP). The application of GMP improved the efficiency of the dark fermentation of food waste. Hydrogen yields reached 102 L/kg of solid waste and 2.3 L/L of liquid waste. The fermentation resulted in the 91-fold reduction in the weight of the solid waste, while the concentration of organics in the liquid waste decreased 3-fold. Our results demonstrated the potential of granular microbial preparations in the production of hydrogen via dark fermentation. Further development of this technology may help to clean up the environment and reduce the reliance on fossil fuels by generating green hydrogen via recycling of household and industrial organic wastes.

Chromium(VI) is one of the most hazardous contaminant of the water and soil environment. Thermodynamic calculations enable to determine the optimal metabolic pathways for microbial extraction of toxic soluble hexavalent chromium compounds from contaminated sewage. The purpose of this research was to predict theoretically and confirm experimentally the possibility of hazardous chromium(VI) removal by hydrogen producing microbiome with simultaneous destruction of multicomponent organic waste and hydrogen synthesis. Gas composition was determined by the standard gas chromatography method. The redox potential (Eh) and рН of the medium were measured potentiometrically by EZODO MP-103 universal ionomer. The Cr(VI) concentration was determined by a photocolorimetric method with 1,5-diphenylcarbazide (DFK). Multicomponent organic waste was effectively destroyed by hydrogen producing microbiome in control conditions (at the absence of chromium). Maximum concentration of H2 was 36% and biohydrogen yield was 81 l/kg of absolutely dry weight of waste. The weight of organic waste was 92 times decreased (Kd=92) during only 82 hours. The hydrogen fermentation cycle was not significantly inhibited by addition of Cr(VI). Thus, the efficiency of waste destruction and biohydrogen yield decreased consequently on 10% (Kd=83) and 7% (75 l/kg of waste) after addition of 50 ppm Cr(VI) to the culture liquid at the beginning of the final phase (50 hours) of the fermentation. As it was expected, the addition of 100 ppm Cr(VI) into the liquid phase during the final fermentation phase (80 hours) caused rapid increase of the redox potential and short-term inhibition of the fermentation process. However, after complete reduction of soluble CrO42- to insoluble Cr(OH)3∙nH2O↓ by hydrogen producing microorganisms, H2 synthesis resumed and metabolic parameters returned to initial values (the Eh was -185 mV and -99 mV after complete extraction of 50 ppm and 100 ppm Cr(VI) consequently). The optimal pathway of microbial detoxification of toxic chromium(VI) compounds was thermodynamically predicted and experimentally confirmed. High efficiency of CrO42- removal by strict anaerobic hydrogen producing microbiome via dark hydrogen fermentation of multicomponent organic waste was demonstrated. The obtained results could be used as the basis for development of novel environmental biotechnology of chromium-containing sewage purification and simultaneous destruction of environmentally hazardous organic waste as well as obtaining of eco-friendly energy carrier – biohydrogen.

Aim. Determination of taxonomic position and resistance to Cd2+, Cu2+, Ni2+, Co2+, CrO42- of isolated bacteria from cadmium-contaminated soils. Methods. Bacterial cultures were isolated by ten-fold dilutions and further cultivation on agarized nutrient medium. Taxonomic position of isolated cultures was determined by molecular-genetic methods using GenBank and BLAST. Bacterial resistance to toxic metals was determined by strains cultivation in liquid medium in the presence of concentration gradient of Cd2+, Cu2+, Ni2+, Co2+, CrO42-. Results. Isolated cultures were highly resistance to cadmium. These bacterial cultures were identified as Brevundimonas vesicularis and Cupriavidus gilardii by phenotypic and molecular-genetic characteristics. Their resistance was in one order higher comparing to generally accepted. Conclusions. Isolated strains are promising for using in novel industrial biotechnologies for metal containing wastewater treatment. Keywords: metalresistance, toxic metals, taxonomic position, Cupriavidus gilardii, Brevundimonas vesicularis.

Aim. To determine species composition and taxonomic position of extremotolerant Antarctic yeast. Methods. The objects of research were yeast from Antarctic soils and phytocenosis, which are stored in the Collection of Extremophilic Microorganisms at the Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine, Kiev. Yeast were grown on malt wort (рН 5.0–5.5, temperature 18–20°С). Isolation of genomic DNA was performed using a commercial kit DNA-sorb; amplification of DNA preparations – use of primers NL1 and NL4; phylogenetic analysis – construction of dendrograms showing the position of the studied strains among closely related and typical species. Results. The analysis have shown a high percentage of similarity (98.4–99.9 %) of 18S rRNA genes sequences of yeast Antarctic strains and yeast sequences from the database GenBank. It was found that yeast strains belonged to phylum Basidiomycota (genera Rhodosporidium, Rhodotorula) and Ascomycota (genus Exophiala). Conclusions. As it was shown by phylogenetic analysis, red yeast S33, S48, S182 clustered with Rhodotorula mucilaginosa; S14 – with Rhodosporidium diobovatum and can be attributed to these species. Extremotolerant black yeast S10, S36 and S237 refer to the species Exophiala nigra. Keywords:Antarctica, extremotolerant yeast, phylogenetic analysis, species composition.

For heterotrophic microorganisms (44 strains) isolated-from the surface film of Lake Baikal, iden- tification was carried out and their. physiological and biochemical characteristics were determined. Com- pared to the water column, diversity of cultured heterotrophs was low, indicating formation of stable micro- bial communities at the air-water interphase interface. Heterotrophic bacteria isolated from the surface mi- crolayer exhibited the enzymatic activity comparable to that for strains form other biofilm associations. Deinococcusfi6us strain NA202 'vas the most active component of the community, capable of utilization of the broadest spectrum of mono- and disaccharides,'sugars, and amino acids. This strain possessed the highest diversity of extracellular enzymes and was the most resistant to UV radiation. The physiological and bio- chemical properties of this strain may-be responsible for its adaptation to survival in extreme conditions of the surface microlayer. Our results improve our understanding of occurrence of UV-resistant strains in freshwater ecosystems.

Purpose To determine resistance to dehydratation of bacteria resistant to UV irradiation. Methods Objects of research - extremophilic bacteria (from Antarctic islands and hypersaline reservoirs of Israel and Crimea). Dehydratation of bacteria was carried out in sealed desiccator; the exposure without access of moisture was 5 weeks, temperature - 22 - 25 °C, humidity - 1 - 4 %. UV irradiation of bacteria was carried out by lamp BUF 15 (A = 254 nm) in the range of 40 - 2400 J/m(2). After cultivation irradiated and not irradiated strains (before and after UV irradiation and before and after drying) we determined the number of cells. Results The extremely resistant to dehydratation (Firmicutes) and extremely sensitive to dehydratation (Proteobacteria, Bacteroidetes) strains was found among the studied bacteria. Most strains of bacteria that were resistant to dehydratation were also resistant to UV irradiation. Survival after dehydratation in these bacteria was 6.32 - 55.26 % and UV LD99.99 240-600 J/m(2). Instead, representatives of Proteobacteria were extremely sensitive to these extreme factors: the cell survival was 0 - 1.6 % after dehydratation and UV LD99.99 80 - 180 J/m(2). Conclusions The results support the hypothesis that between bacteria resistance to electromagnetic radiation (UV) and their resistance to dehydratation there is a correlation.

To determine resistance to dehydratation of bacteria resistant to UV irradiation.Objects of research - extremophilic bacteria (from Antarctic islands and hypersaline reservoirs of Israel and Crimea). Dehydratation of bacteria was carried out in sealed desiccator; the exposure without access of moisture was 5 weeks, temperature - 22 - 25 °C, humidity - 1 - 4 %. UV irradiation of bacteria was carried out by lamp BUF 15 (A = 254 nm) in the range of 40 - 2400 J/m(2). After cultivation irradiated and not irradiated strains (before and after UV irradiation and before and after drying) we determined the number of cells.The extremely resistant to dehydratation (Firmicutes) and extremely sensitive to dehydratation (Proteobacteria, Bacteroidetes) strains was found among the studied bacteria. Most strains of bacteria that were resistant to dehydratation were also resistant to UV irradiation. Survival after dehydratation in these bacteria was 6.32 - 55.26 % and UV LD99.99 240-600 J/m(2). Instead, representatives of Proteobacteria were extremely sensitive to these extreme factors: the cell survival was 0 - 1.6 % after dehydratation and UV LD99.99 80 - 180 J/m(2).The results support the hypothesis that between bacteria resistance to electromagnetic radiation (UV) and their resistance to dehydratation there is a correlation.

Multi-resistant to extreme factors spore-forming bacteria of Bacillus genus are isolated from hypersaline environments of the Crimea (Ukraine) and the Dead Sea (Israel). Phylogenetic analysis showed distinction of dominating extremophilic culturable species in studied regions. In Crimean environments they are B. mojavensis and B. simplex, in the Dead Sea ecosystem--B. subtilis subsp. spizizenii, B. subtilis subsp. subtilis, B. licheniformis and B. simplex. Isolates are simultaneously halotolerant and resistant to UV radiation. Strains isolated from the Dead Sea and the Crimea environments were resistant to UV: LD90 and LD99.99 made 100-170 J/m2 and 750-1500 J/m2 respectively. Spores showed higher UV-resistance (LD99.99-2500 J/m2) than the vegetative cells. However the number of spores made 0.02-0.007% of the whole cell population, and should not significantly affect the UV LD99.99 value. Isolates of both environments were halotolerant in the range of 0.1-10% NaCl and thermotolerant in the range of 20-50 °C, and didn't grow at 15 °C. Survival strategy of spore-forming bacteria from hypersaline environments under high UV radiation level can be performed by spore formation which minimize cell damage as well as efficient DNA-repair systems that remove damages.

For heterotrophic microorganisms (44 strains) isolated-from the surface film of Lake Baikal, iden- tification was carried out and their. physiological and biochemical characteristics were determined. Com- pared to the water column, diversity of cultured heterotrophs was low, indicating formation of stable micro- bial communities at the air-water interphase interface. Heterotrophic bacteria isolated from the surface mi- crolayer exhibited the enzymatic activity comparable to that for strains form other biofilm associations. Deinococcusfi6us strain NA202 'vas the most active component of the community, capable of utilization of the broadest spectrum of mono- and disaccharides,'sugars, and amino acids. This strain possessed the highest diversity of extracellular enzymes and was the most resistant to UV radiation. The physiological and bio- chemical properties of this strain may-be responsible for its adaptation to survival in extreme conditions of the surface microlayer. Our results improve our understanding of occurrence of UV-resistant strains in freshwater ecosystems.

Antarctic plants are stable specific microenvironments for microbial colonization that are still less explored. In this study, we investigated cultivable heterotrophic bacteria and yeasts dominating in plant samples collected from different terrestrial biotopes near Ukrainian Antarctic Base on Galindez Island, maritime Antarctica. Phylogenetic analysis revealed affiliation of the bacterial isolates to genera Pseudomonas, Stenotrophomonas, Brevundimonas, Sporosarcina, Dermacoccus, Microbacterium, Rothia and Frondihabitans, and the yeast isolates to genera Rhodosporidium, Cryptococcus, Leucosporidiella, Candida and Exophiala. Some ecophysiological properties of isolated strains were determined that are important in response to different stresses such as psychro- and halotolerance, UV-resistance and production of hydrolytic enzymes. The majority of isolates (88 %) was found to be psychrotolerant; all are halotolerant. Significant differences in survival subsequent to UV-C radiation were observed among the isolates, as measured by culturable counts. For the bacterial isolates, lethal doses in the range 80-600 J m⁻² were determined, and for the yeast isolates--in the range 300-1,000 J m⁻². Dermacoccus profundi U9 and Candida davisiana U6 were found as most UV resistant among the bacterial and yeast isolates, respectively. Producers of caseinase, gelatinase, β-glucosidase, and cellulase were detected. To the best of our knowledge, this is the first report on isolation of UV resistant strain D. profundi, and Frondihabitans strain from Antarctica, and on detection of cellulase activity in Antarctic yeast strain C. davisiana. The results obtained contribute to clarifying adaptation strategies of Antarctic microbiota and its possible role in functional stability of Antarctic biocenoses. Stress tolerant strains were detected that are valuable for ecological and applied studies.

Multi-resistant to extreme factors spore-forming bacteria of Bacillus genus are isolated from hypersaline environments of the Crimea (Ukraine) and the Dead Sea (Israel). Phylogenetic analysis showed distinction of dominating extremophilic culturable species in studied regions. In Crimean environments they are B. mojavensis and B. simplex, in the Dead Sea ecosystem--B. subtilis subsp. spizizenii, B. subtilis subsp. subtilis, B. licheniformis and B. simplex. Isolates are simultaneously halotolerant and resistant to UV radiation. Strains isolated from the Dead Sea and the Crimea environments were resistant to UV: LD90 and LD99.99 made 100-170 J/m2 and 750-1500 J/m2 respectively. Spores showed higher UV-resistance (LD99.99-2500 J/m2) than the vegetative cells. However the number of spores made 0.02-0.007% of the whole cell population, and should not significantly affect the UV LD99.99 value. Isolates of both environments were halotolerant in the range of 0.1-10% NaCl and thermotolerant in the range of 20-50 °C, and didn't grow at 15 °C. Survival strategy of spore-forming bacteria from hypersaline environments under high UV radiation level can be performed by spore formation which minimize cell damage as well as efficient DNA-repair systems that remove damages.

34 strains of aerobic chemoorganotrophic microorganisms were isolated from 23 soil and plant samples selected from highland biotopes of Ecuador-Andes massif (Papallacta, 4020 m), ash at the foot of the volcano Tungurahua, mountainous jungle (La Favorita, 1600 m), as well as in humid tropic botanical garden (state Puyo, 950 m). In mountain jungle samples the high number of bacteria--10(5)-10(7) CFU/g of sample were represented by 2-5 morphotypes. In highland (4020 m) samples the bacterial counts made from 10(2) to 10(7) CFU/g of sample. The current study describes resistance of isolated strains to high salinity, UV radiation and toxic metal ions. The majority of isolated strains were halotolerant. Isolates from volcanic ash showed high resistance level to UV radiation--LD99,99 made 1000-1440 J/m2; resistance level for isolates from the soil of Puyo Botanical Garden and isolates from rock lichen (Papallacta) LD99,99 made 1160 and 800 J/m2 respectively. Strains isolated from mountain jungle (La Favorita) showed lower UV-resistance. In highland biotopes of Ecuador occurred bacteria resistant to toxic metal ions. The highest resistance to Hg2+ was shown by isolate of lichen from mountain jungle, the maximal growth concentration was 0.025 g/L; to Cr(VI)--by isolate from lichen rock massif--3,0 g/L. Correlation between metal-resistance, halotolerace and UV resistance for studied strains was not detected, probably because of different microbial cell damage/repair mechanisms under the action of these factors.

Phylogenetic analysis of aerobic chemoorganotrophic bacteria of the two extreme regions (Dead Sea and West Antarctic) was performed on the basis of the nucleotide sequences of the 16S rRNA gene. Thermotolerant and halotolerant spore-forming bacteria 7t1 and 7t3 of terrestrial ecosystems Dead Sea identified as Bacillus licheniformis and B. subtilis subsp. subtilis, respectively. Taking into account remote location of thermotolerant strain 6t1 from closely related strains in the cluster Staphylococcus, 6t1 strain can be regarded as Staphylococcus sp. In terrestrial ecosystems, Galindez Island (Antarctic) detected taxonomically diverse psychrotolerant bacteria. From ornithogenic soil were isolated Micrococcus luteus O-1 and Microbacterium trichothecenolyticum O-3. Strains 4r5, 5r5 and 40r5, isolated from grass and lichens, can be referred to the genus Frondihabitans. These strains are taxonomically and ecologically isolated and on the tree diagram form the joint cluster with three isolates Frondihabitans sp., isolated from the lichen Austrian Alps, and psychrotolerant associated with plants F. cladoniiphilus CafT13(T). Isolates from black lichen in the different stationary observation points on the south side of a vertical cliff identified as: Rhodococcus fascians 181n3, Sporosarcina aquimarina O-7, Staphylococcus sp. 0-10. From orange biofilm of fouling on top of the vertical cliff isolated Arthrobacter sp. 28r5g1, from the moss-- Serratia sp. 6r1g. According to the results, Frondihabitans strains most frequently encountered among chemoorganotrophic aerobic bacteria in the Antarctic phytocenoses.

The aerobic chemoorganotrophic bacteria, dominating in soils and phytocenosis of the Antarctic Region, on combination of morphological and biochemical properties belong to several taxons of Bacteria domain. Gram-negative strains 3189, 3415 (fam. Halomonadaceae, Halomonas sp.) and 3088, 3468, 3469 (fam. Moraxellaceae, Psychrobacter sp.) belong to phylum Proteobacteria, to class Gammaproteobacteria. Gram-negative strains 3294 3392 (Rhizobiales, fam. Methylobacteriaceae, Methylobacterium sp.) relate to class Alphaproteobacteria of this phylum. Gram-positive strains 3179, 3275, 3470, 3471 (fam. Microbacteriaceae, Cryobacterium sp.), 3054, 3058, 3411 (fam. Corynebacteriaceae, Corynebacterium sp.) and 3194, 3398 (fam. Micrococcaceae, Micrococcus sp.) relate to phylum Actinobacteria, class Actinobacteria. Thus, the psychrophilic and psychrotolerant Antarctic bacteria (aerobic chemoorganotrophic) isolated from phytocenosis and soils of polar region are characterized by wide taxonomic variety.

Such extreme factors as UV radiation, high temperature and salinity, and also the small amount of accessible water have an influence on microorganisms of coastal ecosystems of the Dead Sea. Resistance to these factors of the microorganisms isolated from ecosystems of this region (vertical steep gorge around the Dead Sea, clay-salt plain and black highly mineralized muds) is studied. Aerobic, chemoorganotrophic, thermotolerant, moderately halophilic bacteria which, according to their morphological and physiological properties, are similar to species Gracilibacillus halotolerans, Salimicrobium album and genus Caryophanon have been isolated from these ecosystems. All strains grew at 0-10% of NaCl in the medium (one strain--at 15% of NaCl), in the range of 30-50 degrees C. Resistance to UV radiation has been revealed in all the investigated bacteria Lethal doses of UV (LD90 and LD99.99) for spore-forming strains of genus Gracilibacillus were 100-170 and 1100-1500 J/m2, respectively; for strain Salimicrobium 6t1 (does not form spores)--70 and 400 J/m2; for the strain lt4 (genus Caryophanon), forming filamentous (or trychomes)--150 and 1400 J/m2. Some strains of genus Gracilibacillus had strong antagonistic effect on conditionally pathogenic test cultures Staphylococcus aureus 209p and Candida albicans UCM Y-690. It is conceivable that resistance of microorganisms of coastal ecosystems of the Dead Sea to extreme factors was generated under the influence of abiotic (physical and chemical) factors typical of this region.

It is shown that the total number of chemoorganotrophic aerobic microorganisms in the Antarctic Region revealed at 1 degree C and 5 degrees C made from 10(4) up to 10(6) cells/g of plant-soil sample of biotopes: grass Deschampcia antarctica, grass Colobanthus, green mosses, crustose black lichens and a biofilm of accretion on vertical rocks. From 10(6) up to 10(8) cells/g of samples were revealed in the same Antarctic samples at 30 degrees C. At 42 degrees C thermotolerant bacteria were either absent, or their quantity was less than 10(4) cells/g of samples. Thus the fraction (part) of the Antarctic microorganisms, which grow at different temperatures, varied: at 1-5 degrees C their part made from 5 to 15%, and at 30 degrees C--from 10 to 45%. At 15-20 degrees C the growth of both psychrophilic/psychrotolerant, and mesophilic microorganisms was observed. When comparing the results of plating of samples from different climatic zones (the Antarctic Region and Ukraine), it is shown that in the Antarctic biotopes in comparison with biotopes of the zone with temperate climate: (1) the total number of microorganisms is lower, (2) quantity of psychrophilic/psychrotolerant bacteria is higher, (3) quantity of mesophilic microorganisms is less, (4) as a result the part psychrophilic/psychrotolerant microorganisms in the total number of microorganisms is much higher. It is evident, that low temperatures, and also daily cycles of freezing and thawing are factors which limit microbial colonization ofAntarctic biotopes.