Candidatus Desulforudis audaxviator

Candidatus Desulforudis audaxviator is a species of bacterium that is notable for its unique habitat and metabolic capabilities. It is a member of the phylum Firmicutes, class Clostridia, and is classified within the family Peptococcaceae. This bacterium was discovered in a deep subsurface environment, specifically in a South African gold mine, at a depth of approximately 2.8 kilometers below the Earth's surface.

Discovery and Habitat

Candidatus Desulforudis audaxviator was first identified in 2008 by a team of researchers led by Dr. Dylan Chivian. The bacterium was found in water samples collected from a fracture zone in the Mponeng gold mine, located near Johannesburg, South Africa. This environment is characterized by extreme conditions, including high temperatures, high pressure, and an absence of sunlight.

The name "audaxviator" is derived from Latin, meaning "bold traveler," reflecting the bacterium's ability to thrive in such an inhospitable environment. The discovery of Candidatus Desulforudis audaxviator has provided significant insights into the potential for life in extreme environments, both on Earth and possibly on other planets.

Metabolism and Physiology

Candidatus Desulforudis audaxviator is a chemolithoautotroph, meaning it derives its energy from the oxidation of inorganic molecules. It is capable of reducing sulfate to sulfide, a process that is coupled with the oxidation of hydrogen. This metabolic pathway allows the bacterium to survive in an environment devoid of organic carbon and sunlight.

The genome of Candidatus Desulforudis audaxviator reveals a complete set of genes necessary for carbon fixation, nitrogen fixation, and sulfate reduction. This indicates that the bacterium is capable of sustaining itself independently, without relying on other organisms for nutrients.

Significance

The discovery of Candidatus Desulforudis audaxviator has significant implications for our understanding of life in extreme environments. It demonstrates the potential for microbial life to exist in isolated and energy-limited ecosystems, such as those found deep within the Earth's crust. This has further implications for the search for extraterrestrial life, particularly on planets and moons with subsurface oceans or other extreme environments.

Also see

• Extremophile
• Deep biosphere
• Chemolithoautotroph
• Sulfate-reducing bacteria

References

• Chivian, D., et al. (2008). "Environmental genomics reveals a single-species ecosystem deep within Earth." Science, 322(5899), 275-278.
• Lin, L. H., et al. (2006). "Long-term sustainability of a high-energy, low-diversity crustal biome." Science, 314(5798), 479-482.