Thermococci

This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these messages) This article relies largely or entirely on a single source. Relevant discussion may be found on the talk page. Please help improve this article by introducing citations to additional sources. Find sources: "Thermococci" – news · newspapers · books · scholar · JSTOR (August 2019) This article includes a list of general references, but it lacks sufficient corresponding inline citations. Please help to improve this article by introducing more precise citations. (August 2019) (Learn how and when to remove this message) This scientific article needs additional citations to secondary or tertiary sources. Help add sources such as review articles, monographs, or textbooks. Please also establish the relevance for any primary research articles cited. Unsourced or poorly sourced material may be challenged and removed. (August 2019) (Learn how and when to remove this message) (Learn how and when to remove this message)

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 Protoarchaea Cavalier-Smith 2002 "Thermococcia" Oren, Parte & Garrity 2016

In taxonomy, the Thermococci are a class of microbes within the Euryarchaeota.^[1]

They live in extremely hot environments, such as hydrothermal vents, and they have optimal growth temperatures above 80 °C. Thermococcus and Pyrococcus (literally "balls of fire") are both obligately anaerobic chemoorganotrophs.

Thermococcus prefers 70–95 °C and Pyrococcus 70-100 °C. Palaeococcus helgesonii, recently discovered in the Tyrrhenian Sea, is an aerobic chemoheterotrophic that grows at temperatures of 45–85 °C with an optimal temperature of 80 °C. Thermococcus gammatolerans sp. nov. was recently discovered in the Guaymas 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 pronounced radioresistance and can survive gamma radiation at 30 kGy.^[2]

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.