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Sergey Bulat * Russian-French GDRI consortium

Searching for tiny life in extreme environments relevant to Jovian’s Europa : Lessons from subglacial ice studies at Lake Vostok (East Antarctica) . Sergey Bulat * Russian-French GDRI consortium. GDRI consortium . Main BIO. PNPI FSBI, St Petersburg, RU Sergey Bulat - PI

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Sergey Bulat * Russian-French GDRI consortium

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  1. Searching for tinylife in extreme environments relevant to Jovian’s Europa: Lessons from subglacial ice studies at Lake Vostok(East Antarctica) SergeyBulat* Russian-French GDRI consortium

  2. GDRI consortium Main BIO • PNPI FSBI, St Petersburg, RU • SergeyBulat - PI • AARI FSBI, St Petersburg, RU • Vladimir Lipenkov - PI • Valery Lukin • VNIIOceangeologia, St Petersburg, RU • GermanLeitchenkov • LGGE CNRS-UJF, Grenoble, FR • Jean Robert Petit - PI • Michel Legrand (DOC) • Université de Bretagne Occidentale, Brest, FR • Mohamed Jebbar • Station Biologique de Roscoff, Roscoff, FR • Dominique Marie • Ecologie Microbienne UCB-Lyon I, Lyon, FR • Philippe Normand Culturing Cell counts Repetition Culturing 2MS3-IKI RAN, Moscow

  3. Working on Earth-known microbial DNA 4 primary [nucleo]bases: cytosine, guanine, adenine and thymine - C, G, A, T  GenBank sequence database

  4. Laminar flow hood 100 DNA/RNA BioCap hood 100 Clean (dust-free) room 10,000

  5. 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) 211 seqsJuly 2011 Contaminant databases 2MS3-IKI RAN, Moscow

  6. Vostok icefor Biology • Authentication offindings by ecology (environmental conditions) REQUIREMENTS: “Everything is everywhere, but, the environment selects” – Baas Becking, 1934 2MS3-IKI RAN, Moscow

  7. A framework for biological studies adopted for Lake Vostok DNA extraction Primary PCR No PCR products

  8. Vostok station (+3488m) (since 1957) (78°S, 106°E) 1260 km from the coast Absolute minimum -89.2°C Average ann. Temp. -55.1°C Lake Vostok (-3663m) RADARSAT, CSA

  9. Vostok vs. EuropaSURFACE SNOW

  10. Vostok Surface snow (0 – 130mup to 4 Kyr) Below 3m the snow is pristine Very clean ‘life-hostile’ environ • Low accumulation – 2.1-2.4g /cm2/a • Low Aeolian dust input • 2 μm mode; 10-15 ppb (summer time) • Harsh irradiation (UV-C etc.) (‘ozone hole’ – Aug-Nov) • + Water-Oxygen freeradicals • Oxidized organics (photochemical reactions at ice-air interface) • Lowfreezing temperatures – below -36oC (-55.1oC ann.) NO FREE (only BOUND) WATER! (6-6.5 cm/a – snow / needles!) 2MS3-IKI RAN, Moscow

  11. Vostok MEGA-snow2010

  12. Vostok MEGA-snow – SURFACE – 500km toward Vostok V500S10 (Vostok500kmSnow2010 (RAE 55) 2MS3-IKI RAN, Moscow

  13. Vostok MEGA-snow – SURFACE – 3.0 km SW away VMS10 (VostokMeteoricSnow2010 (RAE 55) 2MS3-IKI RAN, Moscow

  14. Vostok MEGA-snow2010 RESULTS Vostok Contaminant Library Human Normal Microbiome 2MS3-IKI RAN, Moscow

  15. Vostok MEGA- et Colossal-snow2011

  16. Vostok MEGA-snow2011 PMS11-1 7034.925S, 8124.103E H 2376m • 216km from coastal Progress – PMS11-1 • Crate 23L  5-8L melt • 29kmfrom coastal Progress – PMS11-2 • Crate 23L  5-8L melt PMS11-2 6941.081S, 7633.621E H 865m Sergey Popob 2MS3-IKI RAN, Moscow

  17. CS11 78,4722S, 106,7796E (VostokCollossalSnow2011 (RAE 56) 220L Vostok Colossal-snow2011 2MS3-IKI RAN, Moscow

  18. Vostok MEGA- et Colossal-snow2011 - RESULTS Cell counts 2MS3-IKI RAN, Moscow

  19. Vostok MEGA- et Colossal-snow2011 - RESULTS PCR - phylotypes V4-v8 16S rDNAamplicon sequencing  HA-Pseudomonas sp (alpha-proteo) - 80% 99% Ewingellaamericana(gamma-proteo, Enterobact.) Bradyrhizobium sp(elkani) (alpha-proteo) Clinical specimens including wound, sputum, urine, stool, blood etc. Sources of infection – domestic air conditioning units, ice baths etc. Vostok Contaminant Library Human Normal Microbiome 2MS3-IKI RAN, Moscow

  20. Pre CONCLUSION • Vostok[et 29km from coast!]SURFACE snow containsa few cells / ml - NO CELL populations [lifeless] Background contamination? 2MS3-IKI RAN, Moscow

  21. Vostok vs. EuropaICE CORE Towards the Lake Vostok

  22. SALE Subglacial Antarctic Lake Environments- >386 2MS3-IKI RAN, Moscow Siegert et al., 2005 AGU Chapman conf 2010

  23. LakeVostokknown since 1994 Published in Nature (Kapitsa et al., 1996) Friendly environment? • Deeply ice buried (in dark) – 4 km • High pressure – 337-377bar • Permanently BUT not very cold – -2.65°C • Likely oxygen supersaturated - >70 mg/L up to 700-1300 mg/L RADARSAT, CSA FREE (LIQUID) WATER! 2MS3-IKI RAN, Moscow

  24. No life ISOLATED May host life 2MS3-IKI RAN, Moscow

  25. RADARSAT, CSA Lake Vostoksettings • Hugesubglacial lake (Masolov et al., SCAR OSC2008) • 275 x 65km in size; 15 500 km2 area; 6 100km3 water • Two main basins with the ridge between 150-200 m deep • Average depth - 300m; max depth – ~1650m (south basin) • Water renewal – 80-100Kyr • Buried beneath 2.0-0.8 Myr old 3750-4200 m thickice sheet • Isolated from surface biota for >14 Ma • Age of water (melted ice) - ~1 Ma • No hydrological linksto other lakes 2.0-0.8 Ma years old 2MS3-IKI RAN, Moscow

  26. Vostok ice core 19.02.1990 (78°S, 106°E) North South Meteoric ice 3650m 0.8 Ma 2.0 Ma – 3538m Accretion Melting zone Gases Lake water body 680m Accretion (lake) ice Accr. rate – <10 mm/a 2MS3-IKI RAN, Moscow

  27. 3720 m - Jan 21, 2011 30m left! 2MS3-IKI RAN, Moscow

  28. AccretioniceBIO features NO GAS NO DOC Many oligotrophic lakes have DOC's in the range of 100 to 500 ppb 2MS3-IKI RAN, Moscow

  29. Bacterialmetabolic pathwaysAccretion ice type 1 In mineral inclusions RECALL: Gas content is very low - 0.001 vs. 0.1 g/cm3 2MS3-IKI RAN, Moscow

  30. Type1 Type2 Life prospective in lake ice 1 ? Anaerobic chemolithoautotrophic piezophilic psychrophiles Given a limiting life temperature threshold - -20°C(Astrobiology, 2006, 6, 677-732)

  31. RESULTS Bacteria in [deep] lake ice

  32. 3608BK - Big ‘Kamina’ Mono-crystalline ice 6 x 8.5 x 15 (mm) 3608m 2MS3-IKI RAN, Moscow

  33. 5G2-3608 et 5G2-3646 Big Kamina-2? 2MS3-IKI RAN, Moscow

  34. Vostokcells / phylotypes - update 2010 Glacier flour 2MS3-IKI RAN, Moscow

  35. Cells DOCPhylotypes Vostok ice core Sulfate-reducing bacteria Hydrogen-oxidizing bacteria Methanogenic archaeaSulfur-oxidizing bacteria Both UNCLASSIFIED! 2MS3-IKI RAN, Moscow

  36. General CONCLUSION • Vostok[et 29km from coast!]SURFACE snow - NO CELL populations [lifeless] • DEEPlakeVostokICEcontainsNO CELL populations [lifeless]? With no cracks! 2MS3-IKI RAN, Moscow

  37. Astrobiology implications

  38. Lake Vostok [ice] is a unique TEST area In searching for [tiny] life indices on icy worlds like Jovian Europa

  39. BioLESSONS from Vostok • Work on youngest the least processed at the surface of Europa material (i.e. ocean water ice) flashed out veins or faults (within ridges?) in a radiation shadow 2MS3-IKI RAN, Moscow

  40. Work guide for ice samples delivered to Earth • applying stringent ice sample (and tools to work on) decontamination procedures in clean conditions to meet trace chemistry and Ancient DNA analysis standards • certification of the various environments in contact with the ice samples for biological content (establishment of contaminantlibrary) • implementation of appropriate methods to obtain a signal at as low as possible a detection level • verification of findings through their possible metabolic profiles as deduced from physical/chemical features of the environment under consideration • replication of findings at an independent laboratory (or experiment) within the framework of specialized laboratories 2MS3-IKI RAN, Moscow

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