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J o h n L e i g h L a b | ||||||||
The Lab
Email the Director : John Leigh, Ph.D. leighj@u.washington.edu |
ArchaeaArchaea constitute one of the three domains in the Woesian tree of life along with Bacteria and Eukarya. Archaea are generally like Bacteria in size and shape and can be found in many of the same environments. However, Archaea are more typically known to live in habitats with environmental extremes such as anaerobiosis, low pH, high salt, high temperature, high pressure, or combinations of these. For this reason Archaea are good model organisms for Astrobiologists to understand environmental limits for life and possible life outside of earth. Archaea are distinct from Bacteria in the possession of a simplified version of the transcriptional apparatus that is characteristic of Eukaryotes, and they can serve as model systems for the study of the eukaryal transcription apparatus. However, regulation of transcription is usually more like well-studied bacterial mechanisms. The Archaea contains three kingdoms, Euryarchaeota (includes methanogens and extreme halophiles), Crenarchaeota (usually sulfur dependant hyperthermophiles), and Korarchaeota (hyperthermophiles of which none have yet been isolated). One of the most "extreme" of the Archaea is Pyrolobus fumarii, which can grow at temperatures as high as 113°C and pHs as low as 4.More About Methanococcus maripaludis |