User:Sarahw2/Korarchaeota

Introduction
The Korarchaeota (also referred to as Xenarchaea or Xenarchaeota) are a phylum of Archaea that derive their name from the Greek noun 'koros' or 'kore', meaning youthful man or woman, and the Gree adjective archaios which means ancient. The name Korarchaeota is equivalent to Candidatus Korarchaeota

Taxonomy/Phylogeny
The Korarchaeota are a phylum of the kingdom, Archaea. They are thought to be a phylum that diverged relatively early in the genesis of Archaea among the deep-branching lineages. Korarchaeaota, along with Thaumarchaeota, Aigarchaeota, Crenarchaeota, belong to the TACK superphylum.

Three-domain analyses of obsidian pool sequences have shown that the rDNA sequences of clones pJP27 and pJP78, have about as many signature features in common with Euryarchaeota as with Crenarchaeota (8 vs.6 features) .This suggests that these lineages branch is not either of the two groups but divergent from them and evolve in a rapid way.

Characteristics
Korarchaeota are a phylum under the Archaea domain and therefore exhibit the archaic characteristics such as having a cell wall without peptidoglycan, as well as lipid membranes that are ether-linked. They have a surface layer of paracrystalline protein. This surface layer, known as the S-layer, is densely packed and comprised of 1-2 proteins form various lattice structures and are most likely what maintains the cells’ structural integrity. They are typically rod-shaped, however, it has been found that this morphology can change to be thicker-shaped in the presence of higher sodium dodecyl sulfate (SDS) concentrations. Korarchaeota cells have an ultrathin filamentous morphology that may vary in length. They typically average 15 μm in length and 0.16 μm in diameter but can be seen up to 100 μm long. Some Archaea can fix carbon dioxide through the 3-hydroxypropionate/4-hydroxybutyrate pathway into organic compounds.

Species
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI).

Listed below are the known species of Korarcheota Candidatus Korarchaeota


 * Genus Candidatus Korarchaeota archaeon
 * Genus Candidatus Korarchaeota archaeon NZ13-K
 * Genus Candidatus Korarchaeum
 * Species Candidatus Korarchaeum cryptofilum
 * Candidatus Korarchaeum cryptofilum OPF8
 * Genus Candidatus Methanodesulfokores
 * Species Candidatus Methanodesulfokores washburnensis


 * Genus Korarchaeote SRI-306
 * Genus environmental samples
 * uncultured korarchaeote pBA5
 * uncultured korarchaeote pJP27
 * uncultured korarchaeote pJP78

Ecology
Korarcheota have been discovered in a wide range of environments ranging from terrestrial, including hot springs to marine, including shallow hydrothermal vents and deep-sea hydrothermal vents. Previous research has shown greater diversity of Korarchaea found in terrestrial hot springs compared to marine environments. Korarcheota likely originated in marine environments and then adapted to terrestrial ones.

Geographically, Korarcheota have been found in a variety of locations around the world including Japan, Yellowstone National Park, the Gulf of California, Iceland and Russia.

Korarchaeota are thermophiles, having been found living in conditions of up to 128 degrees Celsius. The lowest temperature they have been found in is 52 degrees Celsius. While they have frequently been observed living in acidic conditions, they have also been found living in conditions up to a pH of 10.

Researchers have identified a virus that can potentially infect Korarcheota.