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Plans for subglacial lake research

Plans for subglacial lake research. Biology Russian (collaborating French in frame of GDRE ‘Vostok’). Plans for subglacial lake research. Vostok Accretion ice 1 and 2 (and lake water) Biology print in unusual extreme environment. Type1. Type2. 3607m. 3612m.

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Plans for subglacial lake research

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  1. Plans for subglacial lake research Biology Russian (collaborating French in frame of GDRE ‘Vostok’) SALE 1, Vienna

  2. Plans for subglacial lake research VostokAccretion ice 1 and 2 (and lake water) Biology print in unusual extreme environment Type1 Type2 3607m 3612m SALE 1, Vienna

  3. Plans for subglacial lake research VostokAccretion ice 1 and 2 (and lake water) Biology print in unusual extreme environment • Investigate the accretion ice type1 at a scale of small ice slices containing mineral/chemical/gas impurities for the presence of indigenouslife trapped by lake sediments SALE 1, Vienna

  4. Search for life signatures in Lake Vostok 16S rRNA gene sequencing Meltwater As it is or concentrating (up to 20 x 103 fold) using 3 Kd filter Direct PCR gDNA extraction (FastPrep-DNA extraction kits) PCR with broad-range universal degenerate primers targeting 16S rRNA gene (bacteria and archaea) Common Nested SALE 1, Vienna

  5. Vostok ice for Biology • Microscopy andpreliminary DNA trials of strictly decontaminated ice samples • Very low biomass • Microscopy - <7 cells/ml (deduced) • SYBR-Green flow cytometry • ~9 cells/ml (lake ice) • ~24 cells/ml(deep glacial ice) • Traces of DNA • Bacteria and Archaea-<10 cells/ml(deduced from PCR) • Fungi -<0.1 cells/ml(deduced from PCR) GIVEN: SALE 1, Vienna

  6. Vostok icefor Biology High chance of ForwardContamination* by reason of the Very Low Biomass PREMISE: * An accidental contamination of other worlds with microbes brought from Earth SALE 1, Vienna

  7. Vostok icefor Biology • Strict ice(and bio)decontaminationprotocolsandclean (dust-free) roomfacilities • Ancient DNA and Trace DNA analyses regulations • Chemistry controls(DOC, ions-indicators) REQUIREMENTS: SALE 1, Vienna

  8. Vostok icefor Biology • Comprehensive Biological controls REQUIREMENTS: • Sham/mock DNA extraction • Negative PCR • Ice core wash water • Lab Environment (dust) • Vostok drill fluid • Outer-core (optionally) SALE 1, Vienna

  9. Negative PCR Sham DNA extraction Ultra-pure water JPL clean room facilities (>393 entries!) Contaminants in Forensic Science Human pathogens and saprophytes Deep drilling contaminants Overall Contaminant Database – 2160 entries SALE 1, Vienna

  10. Indexing contaminantcriteriafor Vostok lake ice findings SALE 1, Vienna

  11. Lake Vostok BIO settings • Giant subglacial lake • 250 x 60km in size; more than 14 000 km2 in square • Two basins with the ridge 150-200 m deep • Max depth – ~1100-1200m (south basin) • Water renewal – 80-100Kyr • Buried beneath 3750-4200 m thickice sheet (3.5 km asl) • Pressure – 337-377 bar • Water temperature – ~ -2.65°C • DOC~17± 7ppbC • No light • Highoxygen tension - 700-1300mg/L (14 mg/L – reference) (accumulation due to glacial ice melting) • Isolated from surface biota for >15 Ma • >0.8 Ma - provided melting feeds the lake • Low salinity - <0.10 ‰

  12. Bacterial phylotypes recovered in Vostok accretion ice - SUMMARY * No nPCR and shDNA extraction clones included SALE 1, Vienna

  13. Vostok lake ice for Biology • Microscopy trials of strictly decontaminated ice samples - Revised • Very low biomass • Microscopy - <7 cells/ml (deduced) • SYBR-Green flow cytometry • ~9 cells/ml (lake ice) ~1 cells/ml ~1 cells/ml SALE 1, Vienna

  14. Vostok lake ice for Biology • Is Lake Vostok* sterile? • According to DAB 10 or USP XXII standards sterility means 0.1-1 cfu/1 ml *provided the lake ice represents whole lake water column, i.e. lake water is not stratified SALE 1, Vienna

  15. Bacterial phylotypes recovered in Vostok accretion ice - SUMMARY Thermophile 50 - 52°C SALE 1, Vienna

  16. Thermophilesin sediment containing accretion ice~15 Kyr-old Laboratories location Taiwan Mid-Atlantic Ridge 2270-2320 m depth SALE 1, Vienna

  17. Geothermal environment in Lake Vostok environment? Biology evidence • Thermophiles (+ mesophiles?) Geology and Geophysics evidence • Rift structure- geological settings • 4He degassing- long-term seismotectonic evidence from • 18O shift - enrichment with the 18O isotope – indication for hydrothermal spring waters SALE 1, Vienna

  18. Geothermalenvironment in deepcrustalfaults within the lake bedrock Seeping solutions from a crust encouraged by seismotectonic events may boost hydrothermal plume which flush out ‘crustal’ thermophilic bacteria and minerals up to their vents. SALE 1, Vienna

  19. SALE 1, Vienna

  20. Bacterial phylotypes recovered in Vostok accretion ice - SUMMARY Thermophile 50 - 52°C * Celine Lavire/Philippe Normand SALE 1, Vienna

  21. Geothermalenvironment in deepcrustalfaults within the lake bedrock West East Crust Crustal faults revealed beneath the Lake Vostok by ‘earthquake exchange waves’ approach Mantle Polar Marine Geological Survey (report 2004) km SALE 1, Vienna

  22. Lake iceBIO features *as compared to glacial ice SALE 1, Vienna

  23. Bacterial metabolic processes in accretion ice type 1 (sediment inclusions, no oxygen) ? H2 oxidation ? Hydrogenophilus thermoluteolus Methanogenic archaea Sulfate-reducing prokaryotes (SRPs) Our 16S rDNA primers match well but were enable to recover No indication for CH4 No indication for H2S

  24. VostokAccretion ice 1CONCLUSION • Contains a tiny amount of DNA(cells?)originating from within the lake bedrock[deep faults](?) Water body SALE 1, Vienna

  25. Studinger et al., 2003 Life potential within the lake bedrock A: Anaerobic chemoautotrophicthermophiles (mesophiles) SALE 1, Vienna

  26. VostokAccretion ice 2CONCLUSION • Seems to be DNA-free (cell-free?) by reason of: • Supposed oxygen burst in the lake which can easily destroys any cells/DNA in a time • No ‘surface’ cells exist which survive transit to the lake and be trapped into the ice 700-1300 mg/L O2 Water body SALE 1, Vienna

  27. OUTLOOK Lake Vostok • Long-term isolated - >15Ma • High pressure • Hyper-oxigenic? – 700-1300 mg/L • Highly oxidized environment? • superoxide, hydrogen peroxide, singlet O, hydroxyl radical etc. (vs. e.g. carotinoids, catalase, superoxide dismutase) • No potential for redox? • No organic carbon (ultra-oligotrophic) • Constantly low but life supporting temp. (-2.65oC) RADARSAT, CSA SALE 1, Vienna

  28. Life potential in lake water RADARSAT, CSA A: Oxyphilic chemoautotrophicpsychrophilic unknown (by energy source) life forms? Hydrogen? SALE 1, Vienna

  29. Plans for subglacial lake research VostokAccretion ice 1 and 2 (and lake water) Biology print in unusual extreme environment • Investigate more young accretion ice type2 (closer to lake water) in search of lake life signatures SALE 1, Vienna

  30. Plans for subglacial lake research VostokAccretion ice 1 and 2 (and lake water) Biology print in unusual extreme environment • Cleanly sample and investigate lake water for indigenous life signatures SALE 1, Vienna

  31. Plans for subglacial lake research NGRIP ‘red’ ice core (SArcticLE?) Control for Lake Vostok water sampling etc • Prove approaches and methods in ice/water sterile [DNA-free] sampling, decontamination,recoveringandprovingindigenous microbial biodiversity SALE 1, Vienna

  32. Plans for subglacial lake research NGRIP ‘red’ ice core (SArcticLE?) Control for Lake Vostok water sampling etc ~5x103 cell/mL No cells Bag 4: 3039m Bag 15: 3045m SALE 1, Vienna

  33. Plans for subglacial lake research Freshwater rift-based Antarctic lakesPositive control for Lake Vostok water/ice

  34. Plans for subglacial lake research Freshwater rift-based Antarctic lakesPositive control for Lake Vostok water/ice • Prove approaches and methods in ice/water sterile [DNA-free] sampling, decontamination,recoveringandprovingindigenous microbial biodiversity SALE 1, Vienna

  35. Plans for subglacial lake research PolarGlacier ice (Vostok – EPICA – NGRIP) Biology print in deep past and bedrock life 121m 3489m SALE 1, Vienna

  36. Plans for subglacial lake research PolarGlacier ice (Vostok – EPICA – NGRIP) Biology print in deep past and bedrock life • Study more young ice (surface snow - 100 Kyr-old) and that of interglacial-glacial periods to estimate the time limit for DNA survival in Antarctic ice SALE 1, Vienna

  37. Plans for subglacial lake research PolarGlacier ice (Vostok – EPICA – NGRIP) Biology print in deep past and bedrock life • Investigate ice horizons with gas contents spikes and other layers to test e.g. bacterial metabolic in situ activity hypothesis SALE 1, Vienna

  38. Plans for subglacial lake research PolarGlacier ice (Vostok – EPICA – NGRIP) Biology print in deep past and bedrock life • Investigate BASAL glacial ice for the presence of indigenous subglacial bedrock life SALE 1, Vienna

  39. Glacial ice with Aeolian dust and bedrock particlesFindings Two confident phylotypes (of 8) • Bacillus sp (Environ clone) or B. arsenicus (arsenic ore) • Psychrobacter glacincola (Polar regions only?) 3483 m(704 Kyr; -9oC) SALE 1, Vienna

  40. Plans for subglacial lake research Temperate Glaciers (Alps – Andes) Positive control for polar ice Illimani (Bolivia) 58m Illimani (Bolivia) 136m SALE 1, Vienna

  41. Plans for subglacial lake research Temperate Glaciers (Alps – Andes) Positive control for polar ice • Study young glacial ice to estimate the time limit for DNA survival in ice (positive control for polar ice) SALE 1, Vienna

  42. Plans for subglacial lake research Temperate Glaciers (Alps – Andes) Positive control for polar ice • Study BASAL glacial ice for the presence of indigenous subglacial bedrock life (positive control for polar ice) SALE 1, Vienna

  43. Plans for subglacial lake research • VostokAccretion ice I and II (and lake water) Biology print in unusual extreme environment • NGRIP ‘red’ ice core (SArcticLE?) • Control for Lake Vostok water sampling etc • Freshwater rift-based Antarctic lakesPositive control for Lake Vostok water/ice • PolarGlacier ice (Vostok – EPICA- NGRIP) Biology print in deep pastand bedrock life • Temperate Glaciers (Alpes – Andes) Positive control for polar iceBiology print of human activity in recent past

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