title: Subglacial Lake Vostok (Antarctica) accretion ice contains a diverse set of sequences from aquatic, marine and sediment-inhabiting bacteria and eukarya.
abstract: Lake Vostok, the 7(th) largest (by volume) and 4(th) deepest lake on Earth, is covered by more than 3,700 m of ice, making it the largest subglacial lake known. The combination of cold, heat (from possible hydrothermal activity), pressure (from the overriding glacier), limited nutrients and complete darkness presents extreme challenges to life. Here, we report metagenomic/metatranscriptomic sequence analyses from four accretion ice sections from the Vostok 5G ice core. Two sections accreted in the vicinity of an embayment on the southwestern end of the lake, and the other two represented part of the southern main basin. We obtained 3,507 unique gene sequences from concentrates of 500 ml of 0.22 µm-filtered accretion ice meltwater. Taxonomic classifications (to genus and/or species) were possible for 1,623 of the sequences. Species determinations in combination with mRNA gene sequence results allowed deduction of the metabolic pathways represented in the accretion ice and, by extension, in the lake. Approximately 94% of the sequences were from Bacteria and 6% were from Eukarya. Only two sequences were from Archaea. In general, the taxa were similar to organisms previously described from lakes, brackish water, marine environments, soil, glaciers, ice, lake sediments, deep-sea sediments, deep-sea thermal vents, animals and plants. Sequences from aerobic, anaerobic, psychrophilic, thermophilic, halophilic, alkaliphilic, acidophilic, desiccation-resistant, autotrophic and heterotrophic organisms were present, including a number from multicellular eukaryotes.
authors.affiliation: Department of Biological Sciences, Bowling Green State University, Bowling Green, Ohio, United States of America.
authors.forename: Yury M
authors.initials: YM
authors.lastname: Shtarkman
authors.forename: Zeynep A
authors.initials: ZA
authors.lastname: Koçer
authors.forename: Robyn
authors.initials: R
authors.lastname: Edgar
authors.forename: Ram S
authors.initials: RS
authors.lastname: Veerapaneni
authors.forename: Tom
authors.initials: T
authors.lastname: D'Elia
authors.forename: Paul F
authors.initials: PF
authors.lastname: Morris
authors.forename: Scott O
authors.initials: SO
authors.lastname: Rogers
mesh_terms: D000864:Antarctic Regions; D001105:Archaea / Q000145:classification / Q000235:genetics / Q000378:metabolism; D001419:Bacteria / Q000145:classification* / Q000235:genetics* / Q000378:metabolism; D017753:Ecosystem; D056890:Eukaryota / Q000145:classification* / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D007053:Ice; D053858:Metabolic Networks and Pathways; D056186:Metagenomics; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014871:Water Microbiology
chemical_list: D007053:Ice; D009584:Nitrogen