Archaea

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Archaea

Evolutionary biology
One of the three domains of living organisms: Archaea, Bacteria and Eukaryota. While Archaea are single-celled, they are unlike bacteria given their independent evolutionary history. Archaea differ from Eukaryota in their ribosomal structure and the presence—in some—of introns in the genome, as well as other features (e.g., different membrane composition).
 
Molecular biology
Archaea are of interest in biotechnology as they have unique biochemical features (e.g., enzymes of theromophiles, such as Taq polymerase, the “workhorse” enzyme of PCR) and are extremely stable at high temperatures. Archaea include metabolic oddities (e.g., extreme halophiles, which live in extremely salty environments), methanogens (which produce methane) and sulphur-dependant extreme thermophiles (which can live in extremely hot environments).

Archaea phyla
• Crenarchaeota
• Euryarchaeota
• Korarchaeota
• Nanoarchaeota
• Thaumarchaeota (recently proposed)

Archaea

( formerly
References in periodicals archive ?
P]) in the Archaean rocks from the SG-3 section determined by the acoustic logging, VSP and calculation methods, is [V.
In 1983, Goossens better described the transition between Archaean greenstone belts and Birrimian volcanic belts, with the huge accumulation of ultramafic rocks (komatiites, etc.
Vice-President, Operations says, "The Oweinat block appears to represent a substantial portion of an essentially unexplored Archaean gold province.
MGS also states that there may also be potential for mineralization derived from hydrothermal fluids associated with an Upper Archaean granodiorite body that lies immediately south of the Ucua Deformation Zone.
Stratabound copper mineralization in the early Archaean Isua supracrustal belt is described.
He published widely on Archaean evolution, the nature and genesis of komatiite-hosted Ni-Cu and orogenic gold deposits, global metallogeny and conceptual targeting of mineral deposits.
which collectively increased their gold output from 98 t in 1980 to 486 t in 1988 and to Third World countries such as the Philippines, Brazil and Chile who increased their production from 40 t to 111 t, while the SADCC region, with similar Archaean gold belts, only managed to increase from 11.
PHOTO : The Serra dos Carajas Iron-deposit, the Salobo copper deposit, the Onca Puma nickel-deposit, the Crixas and Araci gold deposits, as well as many others, were formed during the Archaean and early Proterozioc eras.
TSX VENTURE:AXM) is pleased to announce the award of three new exclusive exploration permits in the Central African Republic covering approximately 2,400 square km of under-explored Archaean and Proterozoic terrains, named Sosso Polipo, Bakala and Bogoin II.
This is only to be expected in a country whose Archaean terrain, in terms of gold yield per square kilometre, is the most productive of its kind in the world.
TSX VENTURE:AXM) is pleased to announce that Aurafrique SARL, a wholly owned group company, has entered into a Mining Convention with the State of the Central African Republic covering exploration, development and mining activities on the Company's Bambari Permits, which cover an area of 2,000 square kilometres of Archaean greenstone belt.
Blackham will have the largest landholding (>600km2) in the Mining Centre and one of Western Australia's major Archaean greenstone belts.