Thermococci

Thermococci
Thermococcus gammatolerans
Scientific classification
Domain:	Archaea
Kingdom:	Euryarchaeota
Phylum:	Euryarchaeota
Class:	Thermococci Zillig and Reysenbach 2002
Order
"Methanofastidiosales" Thermococcales
Synonyms
"Methanofastidiosia"corrig. Nobu et al. 2016 ProtoarchaeaCavalier-Smith 2002 "Thermococcia"Oren, Parte & Garrity 2016

Schematic diagram of theThermococcus gammatoleranscell pictured above.

Pyrococcus furiosus

Intaxonomy,theThermococciare aclassof microbes within theEuryarchaeota.

They live in extremely hot environments, such ashydrothermal vents,and they have optimal growth temperatures above 80 °C.ThermococcusandPyrococcus(literally "balls of fire" ) are both obligatelyanaerobicchemoorganotrophs.

Thermococcusprefers 70–95 °C andPyrococcus70-100 °C.Palaeococcus helgesonii,recently discovered in theTyrrhenian Sea,is anaerobicchemoheterotrophicthat grows at temperatures of 45–85 °C with an optimal temperature of 80 °C. Thermococcus gammatoleranssp. nov. was recently discovered in theGuaymas Basin,and it grows at temperatures from 55–95 °C with an optimal temperature around 88 °C with an optimal pH of 6. It has pronouncedradioresistanceand can survivegamma radiationat 30 kGy.

Thermococcus grows on organic substrates where there is a higher capacity of elemental sulfur. This archaeon mostly grows between temperatures 60–100 degrees Celsius. The average temperature where they thrive is around 85 degrees Celcius.

The DNA structure has a cicular genome with around 2,353 coding sequence, and 2,306 are identified.

See also

• List of Archaea genera

Further reading

• Cavalier-Smith, T (2002)."The neomuran origin of archaebacteria, the negibacterial root of the universal tree and bacterial megaclassification".Int. J. Syst. Evol. Microbiol.52(Pt 1): 7–76.doi:10.1099/00207713-52-1-7.PMID11837318.
• Marguet, Evelyne; Gaudin, Marie; Gauliard, Emilie; Fourquaux, Isabelle; le Blond du Plouy, Stephane; Matsui, Ikuo; Forterre, Patrick (2013). "Membrane vesicles, nanopods and/or nanotubes produced by hyperthermophilic archaea of the genus Thermococcus".Biochemical Society Transactions.41(1): 436–442.doi:10.1042/BST20120293.PMID23356325.
• Woese, CR; Kandler O; Wheelis ML (1990)."Towards a natural system of organisms: proposal for the domains Archaea, Bacteria, and Eucarya".Proc. Natl. Acad. Sci. USA.87(12): 4576–4579.Bibcode:1990PNAS...87.4576W.doi:10.1073/pnas.87.12.4576.PMC54159.PMID2112744.
• Zillig W; Reysenbach AL (2001). "Class IV (sic) [V]. Thermococci class. nov.". In DR Boone; RW Castenholz (eds.).Bergey's Manual of Systematic Bacteriology Volume 1: The Archaea and the deeply branching and phototrophic Bacteria(2nd ed.). New York: Springer Verlag. pp.169.ISBN978-0-387-98771-2.
• Garrity GM; Holt JG (2001)."Phylum AII. Euryarchaeota phy. nov.".In DR Boone; RW Castenholz (eds.).Bergey's Manual of Systematic Bacteriology Volume 1: The Archaea and the deeply branching and phototrophic Bacteria(2nd ed.). New York: Springer Verlag. pp.169.ISBN978-0-387-98771-2.