Methanocaldococcus jannaschii

Methanocaldococcus jannaschii
Scientific classification
Domain: Archaea
Kingdom: Euryarchaeota
Phylum: Euryarchaeota
Class: Methanococci
Order: Methanococcales
Family: Methanocaldococcaceae
Genus: Methanocaldococcus
Species: jannaschii
Synonyms
  • Methanococcus jannaschii (Jones 1983)

Methanocaldococcus jannaschii (formerly Methanococcus jannaschii) is a thermophilic methanogenic archaea in the class Methanococci. It was the first archaeon to have its complete genome sequenced [1] The sequencing identified many genes unique to the archaea. Many of the synthesis pathways for methanogenic cofactors were worked out biochemically in this organism,[2] as were several other archaeal-specific metabolic pathways.

Contents

History

Methanocaldococcus jannaschii was isolated from a hot spring at Woods hole [3]

Sequencing

Methanocaldococcus jannaschii was sequenced by a group at TIGR led by Craig Ventner [4] using whole genome shotgun sequencing. According to Ventner, the unique features of the genome provided strong evidence that there are three domains of life.[5]

Biology and Biochemistry

M. jannaschii is a thermophilic methanogen. It is only capable of growth on carbon dioxide and hydrogen as primary energy sources, unlike many other methanococci (such as Methanococcus maripalidus) which can also use formate as a primary energy source [6]. The genome includes many hydrogenases, such as a 5,10-methenyltetrahydromethanopterin hydrogenase [7], a ferredoxin hydrogenase (eha), and a Coenzyme F420 hydrogenase [8].

Proteomic studies showed that M. jannaschii contains a large number of inteins: 19 were discovered by one study [9]

Many novel metabolic pathways have been worked out in M. jannaschii, including the pathways for synthesis of many methanogenic cofactors , riboflavin , and novel amino acid synthesis pathways . Many information processing pathways have also been studied in this organism, such as an archaeal-specific DNA polymerase family [10].

References

  1. ^ Bult CJ et al. (1996). "Complete genome sequence of the methanogenic archaeon, Methanococcus jannaschii.". Science 273 (5278): 1058-1073. PMID 8688087. 
  2. ^ White R. (2001). "Biosynthesis of the methanogenic cofactors.". Vitamins and Hormones 61: 299-337. PMID 11153270. 
  3. ^ Jones WJ et al (1983). "Methanococcus jannaschii sp. nov., an extremely thermophilic methanogen from a submarine hydrothermal vent". Arch. Microbiol. 136 (4): 254-261. 
  4. ^ Wade N. (23 August 1996). "Deep Sea Yields a Clue to Life's Origin.". New York Times. http://www.nytimes.com/1996/08/23/us/deep-sea-yields-a-clue-to-life-s-origin.html?pagewanted=all&src=pm. 
  5. ^ Wade N. et al. ibid.
  6. ^ Jones et al. ibid.
  7. ^ Lyon EJ, Shima S, Buurman G, Chowdhuri S, Batschauer A, Steinbach K, Thauer RK (January 2004). "UV-A/blue-light inactivation of the 'metal-free' hydrogenase (Hmd) from methanogenic archaea". Eur. J. Biochem. 271 (1): 195–204. doi:10.1046/j.1432-1033.2003.03920.x. PMID 14686932. 
  8. ^ Thauer et al. (2010). "Hydrogenases from Methanogenic Archaea, Nickel, a Novel Cofactor, and H2 Storage". Ann. Rev. Biochem. 79: 507-536. 
  9. ^ Zhu W. et al (2004). "Shotgun Proteomics of Methanococcus jannaschii and Insights into Methanogenesis". J. Proteome Res. 3 (3): 538-548. PMID 15253435. .
  10. ^ Ishino Y. et al.. "A Novel DNA Polymerase Family Found in Archaea". J. bacteriol. 180 (8): 2232-2236. 

External links