[Archaeal diversity in permafrost deposits of Bunger Hills Oasis and King George Island (Antarctica) according to the 16S rRNA gene sequencing].

Archaeal communities of permafrost deposits of King George Island and Bunger Hills Oasis (Antarctica) differing in the content of biogenic methane were analyzed using clone libraries of two 16S rRNA gene regions. Phylotypes belonging to methanogenic archaea were identified in all horizons.

[Fungal diversity in the Antarctic active layer].

Taxonomic diversity of fungi in the samples of the active layer of Antarctica was investigated using conventional microbiological techniques and metagenomic analysis of total DNA extracted from environmental samples. The list of Antarctic microscopic fungi was expanded, including detection of the species representing a portion of the fungal complex, which is nonculturable or sterile on conventional nutrient media.

[Novel halotolerant bacterium from cryopeg in permafrost: description of Psychrobacter muriicola sp. nov].

A novel halotolerant psychrotrophic gram-negative bacterium, strain 2pS, was isolated from lenses of water brine in Arctic permafrost (cryopeg). The optimal growth of the new strain was observed at 16-18 degrees C; the maximal and minimal growth temperatures were 37 degrees C and -2 degrees C, respectively. The pH growth range was 5.

[The structure of micromycete complexes in permafrost and cryopegs of the Arctic].

A comparative study of the structure of micromycete complexes has been performed. The samples of micromycetes were taken by boring from unique habitats: cryopegs (lenses of non-freezing hypersaline water in ancient permafrost horizons) and permafrost Arctic sediments of different age enclosing these cryopegs. The possibility of characterizing the above habitats by the structure of specific complexes of microscopic fungi using qualitative and quantitative indices at extremely low numbers of these organisms was demonstrated.

[Halo- and psychrotolerant Geomyces fungi from arctic cryopegs and marine deposits].

Comparative characterization of Geomyces isolates was performed. The isolates were obtained from Arctic cryopegs and the surrounding ancient marine deposits, from nonsaline permafrost soils, and from temperate environments. Microbiological (cultural and morphological) and molecular criteria were used to confirm the identification of the isolates as Geomyces pannorum.

[Heat shock protein of HSP70 family revealed in some contemporary freshwater Amoebae and in Acanthamoeba sp. from cysts isolated from permafrost samples].

A heat shock protein of HSP70 family was revealed for the first time in trophozoites of Acanthamoeba sp. (strain Am8) excysted from cysts previously isolated from samples of permafrost aging 30,000-35,000 years. The constitutive level of this HSP, shown by immunnoblotting in unstressed trophozoites of the ancient acanthamoebae, much surpassed that in unstressed cells of the three examined species of contemporary freshwater amebae of the genus Amoeba.

[Spectral properties of the green alga Trebouxia--a phycobiont of cryptoendolithic lichens in the high-latitude polar regions of Antarctica].

An algologically pure culture of the green alga Trebouxia, a phycobiont of cryptoendolithic lichens, was isolated from the sandstone samples collected in the high-altitude polar regions of Antarctica. The absorption and the second-derivative absorption spectra of the acetone extract of the Antarctic phycobiont cells were studied in comparison with those of the Trebouxia phycobiont isolated recently from the Parmeliaceae lichen in the Mid-European climatic zone. The cells of the Antarctic phycobiont were characterized by a lower content of chlorophyll a and a higher ratio of chlorophyll b and carotenoids to chlorophyll a as compared to the Mid-European phycobiont.

[The possible contribution of late pleistocene biota to biodiversity in present permafrost zone].

During the last decade a wide range of biological objects, which have preserved their viability for tens and hundreds of thousands of years, was found in the samples of permafrost sediments from North-East Eurasia. Among them are bacteria, fungi, algae, moss spores, seeds of higher plants, protists. Along with physiological mechanisms of cryoconservation and constant low temperature of great importance for long-term preservation of biological objects in permafrost layers are ways of burying the organisms and conditions that prevail before the transition of sediments to the permafrost state.

[The absorption and fluorescence spectra of the cyanobacterial phycobilins of cryptoendolithic lichens in the high-polar region of Antarctica].

The algologically pure cultures of the green-brown cyanobacterium Chroococcidiopsis sp. and three cyanobacteria of the genus Gloeocapsa, the blue-green Gloeocapsa sp.1, the brown Gloeocapsa sp.

[Micromycetes and actinobacteria under conditions of many years of natural cryopreservation].

Almost all of the investigated samples of the Arctic and Antarctic permafrost sediments of different genesis with ages from 5-10 thousand to 2-3 million years were found to contain viable micromycete and bacterial cells. The maximum amounts of viable cells of fungi (up to 10(4) CFU/g air-dried sample) and bacteria (up to 10(7)-10(9) CFU/g air-dried sample) were present in fine peaty sediment samples taken from different depths. The identified micromycetes belonged to more than 20 genera of the divisions Basidiomycota, Ascomycota, and Zygomycota, and some represented mitosporic fungi.