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Nitrososphaerota
The Nitrososphaerota (syn. Thaumarchaeota) are a phylum of the Archaea proposed in 2008 after the genome of ''Cenarchaeum symbiosum'' was sequenced and found to differ significantly from other members of the hyperthermophilic phylum Thermoproteota (formerly Crenarchaeota). Three described species in addition to ''C. symbiosum'' are ''Nitrosopumilus maritimus'', ''Nitrososphaera viennensis'', and ''Nitrososphaera gargensis''. The phylum was proposed in 2008 based on phylogenetic data, such as the sequences of these organisms' ribosomal RNA genes, and the presence of a form of type I topoisomerase that was previously thought to be unique to the eukaryotes. This assignment was confirmed by further analysis published in 2010 that examined the genomes of the ammonia-oxidizing archaea ''Nitrosopumilus maritimus'' and ''Nitrososphaera gargensis'', concluding that these species form a distinct lineage that includes ''Cenarchaeum symbiosum''. The lipid crenarchaeol has been found only in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrososphaeria
The Nitrososphaerota (syn. Thaumarchaeota) are a phylum of the Archaea proposed in 2008 after the genome of '' Cenarchaeum symbiosum'' was sequenced and found to differ significantly from other members of the hyperthermophilic phylum Thermoproteota (formerly Crenarchaeota). Three described species in addition to ''C. symbiosum'' are '' Nitrosopumilus maritimus'', '' Nitrososphaera viennensis'', and '' Nitrososphaera gargensis''. The phylum was proposed in 2008 based on phylogenetic data, such as the sequences of these organisms' ribosomal RNA genes, and the presence of a form of type I topoisomerase that was previously thought to be unique to the eukaryotes. This assignment was confirmed by further analysis published in 2010 that examined the genomes of the ammonia-oxidizing archaea '' Nitrosopumilus maritimus'' and '' Nitrososphaera gargensis'', concluding that these species form a distinct lineage that includes ''Cenarchaeum symbiosum''. The lipid crenarchaeol has been found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrososphaerales
The Nitrososphaerota (syn. Thaumarchaeota) are a phylum of the Archaea proposed in 2008 after the genome of '' Cenarchaeum symbiosum'' was sequenced and found to differ significantly from other members of the hyperthermophilic phylum Thermoproteota (formerly Crenarchaeota). Three described species in addition to ''C. symbiosum'' are '' Nitrosopumilus maritimus'', '' Nitrososphaera viennensis'', and '' Nitrososphaera gargensis''. The phylum was proposed in 2008 based on phylogenetic data, such as the sequences of these organisms' ribosomal RNA genes, and the presence of a form of type I topoisomerase that was previously thought to be unique to the eukaryotes. This assignment was confirmed by further analysis published in 2010 that examined the genomes of the ammonia-oxidizing archaea '' Nitrosopumilus maritimus'' and '' Nitrososphaera gargensis'', concluding that these species form a distinct lineage that includes ''Cenarchaeum symbiosum''. The lipid crenarchaeol has been found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrosopumilus Maritimus
''Nitrosopumilus maritimus'' is an extremely common archaeon living in seawater. It is the first member of the Group 1a Nitrososphaerota (formerly Thaumarchaeota) to be isolated in pure culture. Gene sequences suggest that the Group 1a Nitrososphaerota are ubiquitous with the oligotrophic surface ocean and can be found in most non-coastal marine waters around the planet. It is one of the smallest living organisms at 0.2 micrometers in diameter. Cells in the species ''N. maritimus'' are shaped like peanuts and can be found both as individuals and in loose aggregates. They oxidize ammonia to nitrite and members of ''N. maritimus'' can oxidize ammonia at levels as low as 10 nanomolar, near the limit to sustain its life. Archaea in the species ''N. maritimus'' live in oxygen-depleted habitats. Oxygen needed for ammonia oxidation might be produced by novel pathway which generates oxygen and dinitrogen. ''N. maritimus'' is thus among organisms which are able to produce oxygen in dark. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TEX86
TEX86 is an organic paleothermometer based upon the membrane lipids of mesophilic marine Nitrososphaerota (formerly Marine Group 1 Crenarchaeota). Basics The membrane lipids of Nitrososphaerota are composed of glycerol dialkyl glycerol tetraethers (GDGTs) which contain 0-3 cyclopentane moieties. Nitrososphaerota also synthesise crenarchaeol which contains four cyclopentane moieties and a single cyclohexane moiety and a regio-isomer. The cyclohexane and cyclopentane rings, formed by internal cyclisation of one of the biphytane chains, have a pronounced effect on the thermal transition points of the Nitrososphaerota cell membrane. Mesocosm studies demonstrate that the degree of cyclisation is generally governed by growth temperature. Calibrations Based upon the relative distribution of isoprenoidal GDGTs, Schouten et al. (2002) proposed the tetraether index of 86 carbon atoms (TEX86) as a proxy for sea surface temperature (SST). GDGT-0 is excluded from the calibration as it can ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaea
Archaea ( ; singular archaeon ) is a domain of single-celled organisms. These microorganisms lack cell nuclei and are therefore prokaryotes. Archaea were initially classified as bacteria, receiving the name archaebacteria (in the Archaebacteria kingdom), but this term has fallen out of use. Archaeal cells have unique properties separating them from the other two domains, Bacteria and Eukaryota. Archaea are further divided into multiple recognized phyla. Classification is difficult because most have not been isolated in a laboratory and have been detected only by their gene sequences in environmental samples. Archaea and bacteria are generally similar in size and shape, although a few archaea have very different shapes, such as the flat, square cells of '' Haloquadratum walsbyi''. Despite this morphological similarity to bacteria, archaea possess genes and several metabolic pathways that are more closely related to those of eukaryotes, notably for the enzymes invo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryote
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard archaea. This implies that there are only two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as flagellated phagotrophs. Their name comes from the Greek εὖ (''eu'', "well" or "good") and κάρυον (''karyon'', "nut" or "kernel"). E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proteoarchaeota
"Proteoarchaeota" are a proposed archaeal kingdom thought to be closely related to the Eukaryotes.Approximately the same group is sometimes referred to as TACK after the initial letters of its early-found daughter clades: Thaumarchaeota (now Nitrososphaerota), "Aigarchaeota", Crenarchaeota (now Thermoproteota), and "Korarchaeota". Because of the unsettled phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological s ... of the group, the names "Proteoarchaeota" and TACK may become distinct after further re-organization. Classification The phylogenetic relationship of this group is still under discussion. The relationship of the members is approximately as follows: Notes References Archaea Kingdoms (biology) {{Archaea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crenarchaeol
Crenarchaeol is a glycerol biphytanes glycerol tetraether (GDGT) biological membrane lipid. Together with archaeol, crenarcheol comprises a major component of archaeal membranes. Archaeal membranes are distinct from those of bacteria and eukaryotes because they contain isoprenoid GDGTs instead of diacyl lipids, which are found in the other domains (bacteria, procarya). It has been proposed that GDGT membrane lipids are an adaptation to the high temperatures present in the environments that are home to extremophile archaea Discovery and distribution Archaeal GDGTs were first detected in pelagic waters. Unknown GDGTs were also found in marine sediments and isolated from '' Cenarchaeum symbiosum'', a marine ammonia-oxidizing archaeon that lives in symbiosis with sponges. Following the discovery of GDGTs outside of hydrothermal environments, crenarchaeol was first identified as the major GDGT component in surface sediments and extracts from ''C. symbiosum'' by two-dimensional nuc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenarchaeum Symbiosum
''Cenarchaeum symbiosum'' is a species of Archaea in the genus ''Cenarchaeum'', in the phylum Nitrososphaerota in the domain Archaea Archaea ( ; singular archaeon ) is a domain of single-celled organisms. These microorganisms lack cell nuclei and are therefore prokaryotes. Archaea were initially classified as bacteria, receiving the name archaebacteria (in the Archaeba .... ''C. symbiosum'' is psychrophilic and is found inhabiting marine sponges. Genome The genome of ''C. symbiosum'' is estimated to be 2.02 Million bp in length, with a predicted amount of 2011 genes. Ecology ''Cenarchaeum symbiosum'' is a psychrophillic organism capable of surviving and proliferating at low temperatures usually ranging from 7-19 Celsius. ''C. symbiosum'' has a symbiotic relationship with certain varieties of sponge species, usually living in 10-20 meter depths, typically near California. References Further reading * * * {{Taxonbar, from=Q5058785 Archaea Thermoproteo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylum
In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclature for algae, fungi, and plants accepts the terms as equivalent. Depending on definitions, the animal kingdom Animalia contains about 31 phyla, the plant kingdom Plantae contains about 14 phyla, and the fungus kingdom Fungi contains about 8 phyla. Current research in phylogenetics is uncovering the relationships between phyla, which are contained in larger clades, like Ecdysozoa and Embryophyta. General description The term phylum was coined in 1866 by Ernst Haeckel from the Greek (, "race, stock"), related to (, "tribe, clan"). Haeckel noted that species constantly evolved into new species that seemed to retain few consistent features among themselves and therefore few features that distinguished them as a group ("a self-contained un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrososphaera Viennensis
''Nitrososphaera'' is a mesophilic genus of ammonia-oxidizing Crenarchaeota. The first ''Nitrososphaera'' organism was discovered in garden soils at the University of Vienna leading to the categorization of a new genus, family, order and class of Archaea. This genus is contains three distinct species: '' N. viennensis, Ca. N. gargensis'', and ''Ca N. evergladensis''. ''Nitrososphaera'' are chemolithoautotrophs and have important biogeochemical roles as nitrifying organisms. Phylogeny The ''Nitrososphaera'' genus contains one of the first discovered ammonia-oxidizing archaea (''N. viennensis)''. Only three distinct species of this genus have been identified. Both ''Ca. N. gargensis'', and ''Ca N. Evergladensis'' are known as ''Candidatus,'' which have been discovered and analyzed but have yet been studied in pure culture in a lab. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrososphaera Gargensis
''Nitrososphaera gargensis'' is a non-pathogenic, small coccus measuring 0.9 ± 0.3 μm in diameter. ''N. gargensis'' is observed in small abnormal cocci groupings and uses its archaella to move via chemotaxis. Being an Archaeon, ''Nitrososphaera gargensis'' has a cell membrane composed of crenarchaeol, its isomer, and a distinct glycerol dialkyl glycerol tetraether (GDGT), which is significant in identifying ammonia-oxidizing archaea (AOA). The organism plays a role in influencing ocean communities and food production.Courtens, Emilie Np, Eva Spieck, Ramiro Vilchez-Vargas, Samuel Bodé, Pascal Boeckx, Stefan Schouten, Ruy Jauregui, Dietmar H. Pieper, Siegfried E. Vlaeminck, and Nico Boon. "A Robust Nitrifying Community in a Bioreactor at 50 °C Opens up the Path for Thermophilic Nitrogen Removal." ''The ISME Journal'' (2016) http://www.nature.com/ismej/journal/vaop/ncurrent/full/ismej20168a.htm Discovery ''Nitrososphaera gargensis'' was discovered in a Garga hot spring in Siberi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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