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

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References in periodicals archive ?
Woese's genetic reclassification of life suggested not only that bacteria and archaea are distinct groups, but also that eukaryotes and archaea are more closely related than bacteria and archaea.
Di HJ, Cameron KC, Shen JP, Winefield CS, O'Callaghan M, Bowatte S, He JZ (2009) Nitrification driven by bacteria and not archaea in nitrogen-rich grassland soils.
A novel finding of our study is to quantitatively show a reduction of the total methanogenic archaea population in the yeast-supplemented groups (Figure 2).
in is a brand of Archaea Mobility Services Pvt Ltd and was set up in April 2010 by a team of first generation entrepreneurs with 36 man years of experience in Management Consulting, Corporate Banking and IT Product Development with a mission to “simplify personal mobility”.
When the students get to kingdom Monera, they should have a problem, as organisms in this group are in both domain Archaea and domain Bacteria.
This showed that the actinidic archaea was mediating the biological transmutation of magnesium to calcium.
And, it appears that the number of methane-producing archaea in the Tammar wallaby is less than what we typically see in sheep and cattle.
The revolutionary realization -that all eukarya, including humans, owe their existence to a unique act of fusion in the history of evolution, namely the colonization of a voluminous type of archaea as host/stem cell by single-cellular organisms from the bacterial domain--was decisive.
We have no quantitative data on the community densities of algae, Archaea and Bacteria in the lake prior to the 1979 mixing event, with the exception of a few isolated measurements based on samples collected in 1963-1964 [21].
Eskov (1992) erected the genus Baltarchaea Eskov 1992 for the Baltic amber Archaea conica Koch & Berendt 1854; the type specimen of which is lost, but Wunderlich (2004, photos 66, 67) figured specimens which he considered belong in this genus.
The Third Domain: Untold Story of Archaea and the Future of Biotechnology
Prokaryotic cells, which are represented by the eubacteria and archaea, contain precious little internal compartmentalization and have transcriptionally coupled translation, whereas eukaryotic cells, which compose plants, fungi, algae, animals, and a widely diverse group of unicellular protists, are equipped with a large cadre of intracellular compartments that are functionally specialized for specific intracellular tasks.