Thermophiles are organisms that grow best at temperatures above 45°C, and are found in all three domains of life: Bacteria, Archaea and Eukarya. These heat‐loving microbes inhabit high‐temperature environments such as deep‐sea vents and terrestrial hot springs, where they flourish with an impressive phylogenetic and metabolic diversity. Thermophiles also exist in artificial environments as coal refuse piles and geothermal power plants. To thrive in such environments, thermophiles have numerous physical and biochemical adaptations that maintain the integrity and the function of the cell.

Keywords: thermophiles; extremophiles; diversity; Bacteria; Archaea; Eukarya

Figure 1.

(a) Deep‐sea hydrothermal vent chimney from the East Pacific Rise (Photo courtesy Karen Von Damm); (b) Octopus Spring, Yellowstone National Park. Thermocrinis ruber, a pink‐filament‐forming hyperthermophilic bacterium belonging to the Aquificales was isolated from this hot spring.

Figure 2.

Diagram showing the range of optimal temperature and pH for growth for some representatives of archaeal (red), bacterial (blue) and eukaryotic thermophiles (green).

Figure 3.

Microbial communities in Yellowstone National Park. (a) A microbial mat community from Mammoth Hot Springs showing Thermochromatium (pink) and Chlorobium (green), two anoxygenic phototrophs; (b) a microbial community from Octopus Spring dominated by Thermocrinis sp.; (c) a microbial mat from Nymph Creek dominated by the acidophilic green alga, Cyanidium sp.; (d) a microbial community from the source at Nymph Creek dominated by the acidophilic Aquificales, Hydrogenobaculum sp. Bar is approximately 10 cm.

Figure 4.

Chemical bonds in membrane lipids. (a) Ester linkage typical of Bacteria and Eukarya; (b) Ether linkage typical of Archaea and some hyperthermophilic bacteria.



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How to Cite close
Ferrera, Isabel, and Reysenbach, Anna‐Louise(Sep 2007) Thermophiles. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0000406]