Pyrococcus furiosus

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Pyrococcus furiosus
Scientific classification
Kingdom: Archaea
Phylum: Euryarchaeota
Class: Thermococci
Order: Thermococcales
Family: Thermococcaceae
Genus: Pyrococcus
Species: P. furiosus
Binomial name
Pyrococcus furiosus
Erauso et al. 1993

Pyrococcus furiosus is a heat-requiring extremophile species of Archaea, (procaryotes with a different ancestry than ordinary bacteria--and possibly everything else). It is one of the few organisms identified as possessing enzymes containing tungsten, an element rarely found in biological molecules.


Properties

Pyrococcus furiosus is noted for its rapid doubling time of 37 minutes under its unusual optimal conditions. It appears as mostly regular cocci of 0.8 µm to 1.5 µm diameter with monopolar polytrichous flagellation. It grows between 70 ºC and 103 ºC, with an optimum temperature of 100 ºC, and between pH 5 and 9 (with an optimum at pH 7). It grows well on yeast extract, maltose, cellobiose, ß-glucans, starch, and protein sources (tryptone, peptone, casein and meat extracts). Growth is very slow, or nonexistent, on amino acids, organic acids, alcohols, and most carbohydrates (including glucose, fructose, lactose and galactose).

The ability to grow on polysaccharides (maltose, cellobiose, starch) but not on the monomeric sugars suggests that oligosaccharides with various degrees of polymerization may be imported into the cell, and only afterwards hydrolyzed to glucose.


Discovery

Pyrococcus furiosus was originally isolated anaerobically from geothermally heated marine sediments with temperatures between 90 ºC and 100 ºC collected at the beach of Porto Levante, Vulcano Island, Italy. It was first described by Dr Karl Stetter of the University of Regensburg in Germany, and a colleague, Dr Gerhard Fiala.

Genome

The sequencing of the complete genome of Pyrococcus furiosus was completed in 2001 by scientists at the University of Maryland Biotechnology Institute The Maryland team found that the genome had 1,908 kilobases, coding for some 2,065 proteins.

The extremophile's scientific name

The name Pyrococcus means 'fireball' in Latin, to refer to the extremophile's round shape and ability to grow in temperatures of around 100 degrees Celsius. The species name furiosus means 'rushing', and refers to the extremophile's doubling time.

Uses

The enzymes of Pyrococcus furiosus as would obviously be expected, are extremely thermostable. Consequently DNA Polymerase from Pyrococcus furiosus, are often used in the Polymerase Chain Reaction, with the relevant enzyme known as Pfu. At temperatures where other interfering enzymes are destroyed, the activity of this enzyme remains.

References

  • Fiala G. and Stetter K.O. (1986). "Pyrococcus furiosus sp. nov. represents a novel genus of marine heterotrophic archaebacteria growing optimally at 100°C". Archives of Microbiology 145: 56–61.
  • Robb F.T., Maeder D.L., Brown J.R., DiRuggiero J., Stump M.D., Yeh R.K., Weiss R.B., Dunn D.M. (2001). "Genomic sequence of hyperthermophile, Pyrococcus furiosus: implications for physiology and enzymology". Methods in Enzymology 330: 134–57.