1. Antarctic Extremophiles And Extraterrestrial Life Antarctic Extremophiles And Extraterrestrial Life Kevin R. Sowers Astrobiology Afternoon January 2005 Astrobiology Afternoon January 2005

2. Hyperthermophiles Methanopyrus Methanococcus Methanothermus Methanobacterium Methanosarcina Methanoplanus Methanospirillum CrenarchaeotaEuryarchaeota Archaea Methanolobus Methanohalophilus Methanosaeta Methanobrevibacter Halophiles Eukarya Bacteria

3. Archaea are Extremophiles

4. Alessandro Volta

5. Marine Consortium Sowers & Ferry, 2002

6. Orders of Methanogenic Archaea Methanobacteriales H 2 /CO 2 Methanococcales H 2 /CO 2 Methanomicrobiales H 2 /CO 2 Methanopyrales H 2 /CO 2 Methanosarcinales H 2 /CO 2,CH 3 COOH,CH 3 OH, MMA,DMA,TMA,DMS Methanobacteriales H 2 /CO 2 Methanococcales H 2 /CO 2 Methanomicrobiales H 2 /CO 2 Methanopyrales H 2 /CO 2 Methanosarcinales H 2 /CO 2,CH 3 COOH,CH 3 OH, MMA,DMA,TMA,DMS 4H 2 + CO 2 CH 4 + 2H 2 O

7. Photosynthesis

8. Chemosynthesis

9. Mineral nutrients e donors: H 2 e acceptor: CO 2 Anoxic atmosphere Water Mineral nutrients e donors: H 2 e acceptor: CO 2 Anoxic atmosphere Water Methanogen Growth Requirements

10. Surface gravity = 3.8 m s -2 (~ 1/3 rd Earth’s gravity) Current surface temperatures – –87 to 25 o C (atmosphere) -70 to 10 o C (soil temperatures) Atmospheric composition – predominantly CO 2 Life in Extreme Environments Mars

11. 80% of Earth’s Biosphere < 5 o C

12. Mars Geology

13. Water on Mars 4.5 b 3.8 b Present

14. Kaiser, 1995 Deep Subsurface Microbiology

15. marine salinity maximum depth 25 m anaerobic below 10-12 m 2 to 3° C annually marine salinity maximum depth 25 m anaerobic below 10-12 m 2 to 3° C annually Ace Lake - Antarctica

16. Methanococcoides burtonii -T min 1.7˚C T max 30˚C Methanococcoides burtonii -T min 1.7˚C T max 30˚C Methanogenium frigidum - T min 0˚C T max : 18˚C Methanogenium frigidum - T min 0˚C T max : 18˚C Cold-Adapted Methanogens

17. Low Temperature Limits M. frigidumM. burtonii

18. Simulated Arctic Conditions Lowest temperature for growth Effects of low temperature on metabolism Effects of low temperature on survival Lowest temperature for growth Effects of low temperature on metabolism Effects of low temperature on survival

19. Mesophile vs Psychrophile s

20. Subzero Adaptation

21. Methanogenium frigidum 1.6 Mb Methanococcoides burtonii 2.7 Mb (incomplete sequences) Methanogenium frigidum 1.6 Mb Methanococcoides burtonii 2.7 Mb (incomplete sequences) Genomic Analyses

22. Cold-shock proteins Decreased protein surface charge Cold-shock proteins Decreased protein surface charge Cold Adaptation Mechanisms

23. What are the physiochemical limits? Nutrient requirements Temperature Water Radiation Nutrient requirements Temperature Water Radiation

24. Contributors & Collaborators - Sheridan MacAuley (COMB) - Rick Cavicchioli (UNSW) - Iain Neill Reid (STSI) - Sheridan MacAuley (COMB) - Rick Cavicchioli (UNSW) - Iain Neill Reid (STSI)