Scientists Discover Analog for Extraterrestrial Life in Idaho Hot Spring

Archaea in the News

A hydrogen-based subsurface microbial community dominated by methanogens: Nature Scientist May Have Discovered a Model for Extraterrestrial Life, Washington Post Found: Life on Earth That Could Exist on Mars, New York Times (by Associated Press) Scientists Find New Kind of Microbe, New York Times (by Associated Press) UMass Researchers Find Environment on Earth that Mimics Mars Geochemically and Supports Ancient Life Form, NASA Press Release

Archaea Illustration

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U.S. Geological Survey (USGS) scientist Frank Chapelle and his colleagues from the USGS and the University of Massachusetts have discovered a potential analog for life on other planets. The scientists discovered a unique community of microscopic organisms known as Archaea thriving deep in the subsurface source of a hot spring in Idaho. Archaea, a class of microscopic organisms that were once thought to be bacteria, are unique because unlike most life on Earth that relies on oxygen to breathe and organic carbon as a food source (such as decaying plants), Archaea live on a diet of hydrogen and carbon dioxide. Therefore, scientists think Archaea-type microorganisms could exist in worlds without organic carbon, such as Mars or Europa. Archaea are prevalent in Earth's subsurface where oxygen does not exist but are usually found in small numbers compared to more competitive bacteria. For example, the microorganisms (methanogens) that degrade contaminants at chemical and oil spills and produce methane are Archaea. This is the first documented case of a microbial community completely dominated by Archaea -- no other known life form could exist under such harsh conditions.

The methods that were developed to study the fluids and microorganisms, including Archaea, in the hot spring area are presently being used by the USGS Toxic Substances Hydrology Program to study the biodegradation of a chlorinated solvent spill in fractured rock at the Naval Air Warfare Center (NAWC) Research Site, West Trenton, NJ. These methods will enable site managers to understand how microbial populations adapt to chemical stresses, and thus how these microbes contribute to the detoxification of pollutants. The results of this investigation of the microorganisms (Archaea and bacteria) at the NAWC Site will one day lead to the development of subsurface contaminant cleanup technology that exploits the power of these unique microorganisms.

Reference

Chapelle, F.H., O'Neill, K., Bradley, P.M., Methe, B.A., Ciufo, S.A., Knobel, L.L., and Lovley, D.R., 2002, A hydrogen-based subsurface microbial community dominated by methanogens: Nature, v. 415, no. 6869, p. 312-315, doi:10.1038/415312a.

Information on Toxics Program Fractured Rock Investigations

• Geochemical and Microbiological Processes that Affect Migration and Natural Attenuation of Chlorinated Solvents in Fractured Sedimentary Rock -- Naval Air Warfare Center (NAWC) Research Site, West Trenton, NJ
• Multidisciplinary Characterization of Fluid Flow and Solute Transport in Fractured Rock -- Mirror Lake, New Hampshire

Information on Toxics Program Microbiological Investigations

• Processes that Control the Natural Attenuation of Chlorinated Solvents
  • Microbial Degradation of Chloroethenes in Ground Water Systems
  • Application of Molecular Methods in Microbial Ecology to Understand the Natural Attenuation of Chlorinated Solvents
• Microbiology and Molecular Ecology of Biogeochemical Cycles in Aquatic Environments
• Bacteria-Contaminant Interactions
• Organic Compounds in Near-Surface Environments: Understanding Fate in a Changing Biogeochemical Landscape

Related Headlines

• New Microorganism Discovered that Survives on Arsenic in an Extremely Harsh Environment

Information on Microbiology

• Information on Archaea from the American Society for Microbiology
• An Introduction to Archaea from the Department of Plant Biology at University of California, Berkeley
• USGS Microbiology Laboratory, Columbus, Ohio
• USGS Microbiology Research: Activity, Biogeochemistry, and Transport in Water
• U.S. Environmental Protection Agency's Microbiology Home Page
• U.S. Department of Energy's Microbial Genome Program
• Archaea Taxonomy from the National Institutes of Health

Information on the Potential for Extraterrestrial Life

• Live On Mars? Do Martians Exist?, Jet Propulsion Laboratory, National Aeronautics and Space Administration
• Mars Meteorite Home Page, Jet Propulsion Laboratory, National Aeronautics and Space Administration
• The Planetary Society
• The SETI (Search for Extraterrestrial Intelligence) Institute
• USGS Space Science
• National Science Foundation's Life in Extreme Environments Program
  
  

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