NASA Astrobiology Institute (NAI)

1. Molecular Signatures of Life on the Edge (DDF project)

   Project Investigators: Christopher House, Jason Dworkin, Sorel Fitz-Gibbon

   Other Project Members

   Zhidan Zhang (Research Staff)

   Moshe (Mathew) Rhodes (Doctoral Student)

   Andreas Teske (Collaborator)

   Kat Dawson (Doctoral Student)

   Aharon Oren (Collaborator)

   Oded Beja (Collaborator)

   Summary

   We have investigated the Dead Sea, as a possible analog of early Mars environments -- slightly acidic and highly saline. We have used metagenomics, lipid analysis, and amino acid analysis.

   Astrobiology Roadmap Objectives:

   • Objective 2: Develop and test plausible pathways by which ancient counterparts of membrane systems, proteins and nucleic acid were synthesized from simpler precursors and assembled into protocells.
   • Objective 5: Describe the sequences of causes and effects associated with the development of Earth's early biosphere and the global environment.
   • Objective 5: Describe the sequences of causes and effects associated with the development of Earth's early biosphere and the global environment.
   • Objective 5: Describe the sequences of causes and effects associated with the development of Earth's early biosphere and the global environment.
   • Objective 7: Identify the environmental limits for by examining biological adaptations to extremes in environmental conditions.

   Project Progress

   We have moved forward on field work first. We have also completed half of our metagenomics sequencing including half of a 454 plate for the modern Dead Sea, half of a plate from the 1992 Dead Sea. We also have amino acid analysis and lipid analysis.

   Cross-Team Collaborations

   The project involved Aharon Oren (Hebrew University of Jerusalem), Oded Beja, (Technion), Andreas Teske (UNC; part of MBL team), Sorel T. Fitz-Gibbon (UCLA), Jason Dworkin (Goddard). These researchers have been an important part of our work contributing expertise and techniques.

Publications

Rhodes, M., Fitz-Gibbon, S., Oren, A. & House, C.  (2008).  Molecular Biosignatures of Life on the Edge [Abstract].  Astrobiology, 2(8):474.