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Among the most interesting targets for Astrobiology research are the polar ice caps and the permafrost of Mars and
the ice and liquid water bodies that may lie beneath the frozen crusts of comets, the icy moons of Jupiter (Europa, Io
and Ganymede) and Saturn (Titan and Enceladus). The permanently ice-covered lakes of Antarctica, such as Lake
Vostok and Lake Untersee, provide some of the best terrestrial analogues for these targets. The 2008 International
Tawani Schirmacher Oasis/Lake Untersee Expeditions have been organized to conduct studies of novel microbial
extremophiles and investigate the biodiversity of the glaciers and ice-covered lakes of Dronning Maud Land, East
Antarctica.
This paper describes the preliminary analysis of the anaerobic microbial extremophiles isolated from samples
collected during the 2008 International Schirmacher Oasis Antarctica Reconnaissance Expedition. These samples
showed great diversity of psychrophlic and psychrotolerant bacteria. Six new anaerobic strains have been isolated in
pure cultures and partially characterized. Two of them (strains ARHSd-7G and ARHSd-9G) were isolated from a
small tidal pool near the colony of African Penguins Spheniscus demersus. Strain ARHSd-7G was isolated on
mineral anaerobic medium with 3 % NaCl, pH 7 and D-glucose, it has motile, vibrion shape cells, and is Gram
variable. Strain ARHSd-9G grew on anaerobic, alkaline medium with pH 9 and 1 % NaCl at 3°C. The substrate was
D-glucose supplemented with yeast extract (0.05 %). Cells of strain ARHSd-9G had morphology of straight or
slightly curved elongated rods and demonstrated unusual optical effects under dark-field visible light microscopy.
The cells were spore-forming and Gram positive. From the mat sample collected near Lake Zub, the new strain LZ-3
was isolated in pure culture at 3°C. Strain LZ-3 was anaerobic and grew on 0.5 % NaCl mineral medium with Dglucose
as a substrate. The gram positive cells were spore-forming. They exhibited a distinctive morphology of large
rods with rounded ends and size 1x10 μm. From the sample of ice sculpted by wind and melting by solar heating,
containing many entrained black rocks collected near Lake Podprudnoye the new strain ISLP-22 was isolated in
pure culture. The cells of this strain had vibrion shape and were spore-forming and had "baseball bat" shapes). This
culture preferred 0.1 % NaCl mineral anaerobic medium and grew rapidly at 3 °C. Currently, all strains are under
physiological study and phylogenetic analysis.
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