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Life Form
Life form (also spelled life-form or lifeform) is an entity that is living, such as plants (flora) and animals (fauna). It is estimated that more than 99% of all species that ever existed on Earth, amounting to over five billion species, are extinct. Earth is the only celestial body known to harbor life forms. No form of extraterrestrial life has ever been discovered. Archaea * Archaea – a domain of single-celled microorganisms, morphologically similar to bacteria, but they possess genes and several metabolic pathways that are more closely related to those of eukaryotes, notably the enzymes involved in transcription and translation. Many archaea are extremophiles, which means living in harsh environments, such as hot springs and salt lakes, but they have since been found in a broad range of habitats. ** Thermoproteota – a phylum of the Archaea kingdom. Initially *** Thermoprotei **** Sulfolobales – grow in terrestrial volcanic hot springs with optimum growth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanobacteriales
In taxonomy, the Methanobacteriales are an order of the Methanobacteria. Species within this order differ from other methanogens in that they can use fewer catabolic substrates and have distinct morphological characteristics, lipid compositions, and RNA sequences. Their cell walls are composed of pseudomurein. Most species are Gram-positive with rod-shaped bodies and some can form long filaments. Most of them use formate to reduce carbon dioxide, but those of the genus ''Methanosphaera'' use hydrogen to reduce methanol to methane. Phylogeny The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). See also * List of Archaea genera This article lists the genera of the Archaea. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). Phylogeny ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Korarchaeota
In taxonomy, the Korarchaeota are a phylum of the Archaea. The name is derived from the Greek noun koros or kore, meaning ''young man'' or ''young woman,'' and the Greek adjective archaios which means ''ancient.'' They are also known as Xenarchaeota. Taxonomy Korarchaeota is regarded as a phylum, which itself is part of the archaeal TACK superphylum which encompasses Thaumarchaeota (now Nitrososphaerota), " Aigarchaeota", Crenarchaeota (now Thermoproteota), and "Korarchaeota". Species * "''Candidatus'' Korarchaeum cryptofilum" Elkins et al. 2008 * "''Candidatus'' Methanodesulfokores washburnensis" McKay et al. 2019 Phylogeny Analysis of their 16S rRNA gene sequences suggests that they are a deeply branching lineage that does not belong to the main archaeal groups, Thermoproteota and Euryarchaeota. Analysis of the genome of one korarchaeote that was enriched from a mixed culture revealed a number of both Crenarchaeota- and Euryarchaeota-like features and supports the hypothesi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halophiles
The halophiles, named after the Greek word for "salt-loving", are extremophiles that thrive in high salt concentrations. While most halophiles are classified into the domain Archaea, there are also bacterial halophiles and some eukaryotic species, such as the alga '' Dunaliella salina'' and fungus ''Wallemia ichthyophaga''. Some well-known species give off a red color from carotenoid compounds, notably bacteriorhodopsin. Halophiles can be found in water bodies with salt concentration more than five times greater than that of the ocean, such as the Great Salt Lake in Utah, Owens Lake in California, the Urmia Lake in Iran, the Dead Sea, and in evaporation ponds. They are theorized to be a possible analogues for modeling extremophiles that might live in the salty subsurface water ocean of Jupiter's Europa and similar moons. Classification Halophiles are categorized by the extent of their halotolerance: slight, moderate, or extreme. Slight halophiles prefer 0.3 to 0.8 M (1.7 to 4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoplasmatales
In taxonomy, the Thermoplasmatales are an order of the Thermoplasmata. All are acidophiles, growing optimally at pH below 2. '' Picrophilus'' is currently the most acidophilic of all known organisms, being capable of growing at a pH of -0.06. Many of these organisms do not contain a cell wall, although this is not true in the case of '' Picrophilus''. Most members of the Thermotoplasmata are thermophilic. Phylogeny The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information The National Center for Biotechnology Information (NCBI) is part of the United States National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. Th ... (NCBI). See also * List of Archaea genera References * Further reading Scientific journals * * * * Scientific books * * Scientific database ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoplasmata
In taxonomy, the Thermoplasmata are a class of the Euryarchaeota. All are acidophiles, growing optimally at pH below 2. '' Picrophilus'' is currently the most acidophilic of all known organisms growing at a minimum pH of 0.06. Many of these organisms do not contain a cell wall, although this is not true in the case of '' Picrophilus''. Most members of Thermotoplasmata are thermophilic. Phylogeny The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information The National Center for Biotechnology Information (NCBI) is part of the United States National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. Th ... (NCBI). See also * List of Archaea genera References Further reading Scientific journals * * * * Scientific books * * Scientific databases External links A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermococcales
In taxonomy, the Thermococcales are an order of microbes within the Thermococci. The species within the Thermococcales are used in laboratories as model organisms. All these species are strict anaerobes and can ferment sugars as sources of carbon, but they also need elemental sulfur Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formul .... See also * List of Archaea genera References Further reading * * * * * External links Archaea taxonomic orders Euryarchaeota {{Euryarchaeota-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermococci
In taxonomy, the Thermococci are a class of microbes within the Euryarchaeota.See the NCBIbr>webpage on Thermococci Data extracted from the They live in extremely hot environments, such as hydrothermal vents, and they have optimal growth temperatures above 80 °C. '' Thermococcus'' and '' Pyrococcus'' (literally "balls of fire") are both obligately anaerobic chemoorganotrophs. ''Thermococcus'' prefers 70-95 °C and ''Pyrococcus'' 70-100 °C. '' Palaeococcus helgesonii'', recently discovered in the Tyrrhenian Sea, is an aerobic chemoheterotrophic that grows at temperatures of 45-85 °C with an optimal temperature of 80 °C. '' Thermococcus gammatolerans'' sp. nov. was recently discovered in the Guaymas Basin, and it grows at temperatures from 55-95 °C with an optimal temperaturearound 88 °C with an optimal pH of 6. It has pronounced radioresistance and can survive gamma radiation A gamma ray, also known as gamma radiation (symb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanopyrales
In taxonomy, the Methanopyrales are an order of microbes within the class methanopyri. It contains only one family, Methanopyraceae, one genus, Methanopyrus, and one species, Methanopyrus kandleri. This species is chemolithoautotrophic and its cells are bacillus in form. It grows comfortably at temperatures of 98 °C and can survive at temperatures as high as 110 °C, making it the most thermophilic known methanogen. Strain 116 can survive at up to 122 °C. They live in hydrothermal vents and were first discovered on the walls of a black smoker in the Gulf of California, at the depth of 2000 metres. They are similar to Methanobacteriales, but unlike other methanogenic archaea, their cell walls contain pseudomurein Pseudopeptidoglycan (also known as pseudomurein;White, David. (1995) ''The Physiology and Biochemistry of Prokaryotes'', pages 6, 12-21. (Oxford: Oxford University Press). . PPG hereafter) is a major cell wall component of some Archaea that differs .... ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanopyri
In taxonomy, the Methanopyri are a class of the Euryarchaeota Euryarchaeota (from Ancient Greek ''εὐρύς'' eurús, "broad, wide") is a phylum of archaea. Euryarchaeota are highly diverse and include methanogens, which produce methane and are often found in intestines, halobacteria, which survive extre ....See the NCBIbr>webpage on Methanopyri Data extracted from the References Further reading Scientific journals * * Scientific books * * Scientific databases External links Archaea classes Euryarchaeota {{Euryarchaeota-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanosarcinales
In taxonomy, the Methanosarcinales are an order of the Methanomicrobia. Large amounts of methane are produced in marine sediments but are then consumed before contacting aerobic waters or the atmosphere. Although no organism that can consume methane anaerobically has ever been isolated, biogeochemical evidence indicates that the overall process involves a transfer of electrons from methane to sulphate and is probably mediated by several organisms, including a methanogen (operating in reverse) and a sulfate-reducer (using an unknown intermediate substrate). Organisms placed within the order can be found in freshwater, saltwater, salt-rich sediments, laboratory digestors, and animal digestive systems. Most cells have cell walls that lack peptidoglycan and pseudomurein. They are strictly anaerobic and survive by producing methane. Some species use acetate as a substrate and others use methyl compounds, such as methyl amines and methyl sulfates. Phylogeny See also * List of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanomicrobia
In the taxonomy of microorganisms, the Methanomicrobia are a class of the Euryarchaeota. Phylogeny The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). See also * List of Archaea genera This article lists the genera of the Archaea. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). Phylogeny National Center for ... Further reading Scientific journals * * Scientific books * * Scientific databases External links References Archaea classes Euryarchaeota {{Euryarchaeota-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
