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Promethearchaeum Syntrophicum
Promethearchaeota is the sole phylum of the kingdom Promethearchaeati, the kingdom from which the eukaryotes emerged. The phylum has one valid class: Promethearchaeia. The phylum includes all members of the group previously named Deep Sea Archaeal Group, also known as Marine Benthic Group B. A phylogenetic analysis disclosed a monophyletic grouping of the Promethearchaeota with the eukaryotes. The analysis revealed several genes with cell membrane-related functions. The presence of such genes support the hypothesis of an archaeal host for the emergence of the eukaryotes; the eocyte-like scenarios. Promethearchaeota was introduced in 2015 after the identification of a candidate genome in a metagenomic analysis of a mid-oceanic sediment sample. This analysis suggests the existence of a genus of unicellular life dubbed ''Lokiarchaeum''. The sample was taken near a hydrothermal vent at a vent field known as Loki's Castle located at the bend between Mohns/Knipovich ridge in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Prokaryotic Names With Standing In Nomenclature
List of Prokaryotic names with Standing in Nomenclature (LPSN) is an online database that maintains information on the naming and taxonomy of prokaryotes, following the taxonomy requirements and rulings of the International Code of Nomenclature of Prokaryotes. The database was curated from 1997 to June 2013 by Jean P. Euzéby. From July 2013 to January 2020, LPSN was curated by Aidan C. Parte. In February 2020, a new version of LPSN was published as a service of the Leibniz Institute DSMZ, thereby also integrating the Prokaryotic Nomenclature Up-to-date service and since 2022 LPSN is interconnected with the Type (Strain) Genome Server (TYGS), DSMZ's high-throughput platform for accurate genome-based taxonomy. See also * Code of Nomenclature of Prokaryotes Described from Sequence Data References External links List of Prokaryotic names with Standing in Nomenclature [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocyte Hypothesis
The eocyte hypothesis in evolutionary biology proposes that the eukaryotes originated from a group of prokaryotes called eocytes (later classified as Thermoproteota, a group of archaea). After his team at the University of California, Los Angeles discovered eocytes in 1984, James A. Lake formulated the hypothesis as "eocyte tree" that proposed eukaryotes as part of archaea. Lake hypothesised the tree of life as having only two primary branches: prokaryotes, which include Bacteria and Archaea, and karyotes, that comprise Eukaryotes and eocytes. Parts of this early hypothesis were revived in a newer two-domain system of biological classification which named the primary domains as Archaea and Bacteria. Lake's hypothesis was based on an analysis of the structural components of ribosomes. It was largely ignored, being overshadowed by the three-domain system which relied on more precise genetic analysis. In 1990, Carl Woese and his colleagues proposed that cellular life consists of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Transfer
Horizontal gene transfer (HGT) or lateral gene transfer (LGT) is the movement of genetic material between organisms other than by the ("vertical") transmission of DNA from parent to offspring (reproduction). HGT is an important factor in the evolution of many organisms. HGT is influencing scientific understanding of higher-order evolution while more significantly shifting perspectives on bacterial evolution. Horizontal gene transfer is the primary mechanism for the spread of antibiotic resistance in bacteria, and plays an important role in the evolution of bacteria that can degrade novel compounds such as human-created pesticides and in the evolution, maintenance, and transmission of virulence. It often involves temperate bacteriophages and plasmids. Genes responsible for antibiotic resistance in one species of bacteria can be transferred to another species of bacteria through various mechanisms of HGT such as transformation, transduction and conjugation, subsequently arming ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domain (biology)
In biological taxonomy, a domain ( or ) (Latin: ''regio''), also dominion, superkingdom, realm, or empire, is the highest taxonomic rank of all organisms taken together. It was introduced in the three-domain system of taxonomy devised by Carl Woese, Otto Kandler and Mark Wheelis in 1990. According to the domain system, the tree of life consists of either three domains, Archaea, Bacteria, and Eukarya, or two domains, Archaea and Bacteria, with Eukarya included in Archaea. In the three-domain model, the first two are prokaryotes, single-celled microorganisms without a membrane-bound nucleus. All organisms that have a cell nucleus and other membrane-bound organelles are included in Eukarya and called eukaryotes. Non-cellular life, most notably the viruses, is not included in this system. Alternatives to the three-domain system include the earlier two-empire system (with the empires Prokaryota and Eukaryota), and the eocyte hypothesis (with two domains of Bacteria and A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genes
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Candidatus Prometheoarchaeum Syntrophicum SEM Cryo
In prokaryote Nomenclature codes, nomenclature, ''Candidatus'' (abbreviated ''Ca.''; Latin for "candidate of Roman office") is used to name prokaryotic taxa that are well characterized but yet-Microbiological culture, uncultured. Contemporary sequencing approaches, such as 16S ribosomal RNA sequencing or metagenomics, provide much information about the analyzed organisms and thus allow identification and characterization of individual species. However, the majority of prokaryotic species remain uncultivable and hence inaccessible for further characterization in ''in vitro'' study. The recent discoveries of a multitude of candidate taxa has led to candidate phyla radiation expanding the Tree of life (biology), tree of life through the new insights in bacterial diversity. Nomenclature History The initial International Code of Nomenclature of Prokaryotes (ICNP) as well as early revisions did not account for the possibility of identifying prokaryotes which were not yet cultivabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loki
Loki is a Æsir, god in Norse mythology. He is the son of Fárbauti (a jötunn) and Laufey (mythology), Laufey (a goddess), and the brother of Helblindi and Býleistr. Loki is married to the goddess Sigyn and they have two sons, Narfi (son of Loki), Narfi or Nari and Váli (son of Loki), Váli. By the jötunn Angrboða, Loki is the father of Hel (being), Hel, the wolf Fenrir and the world serpent Jörmungandr. In the form of a mare, Loki was impregnated by the stallion Svaðilfari and gave birth to the eight-legged horse Sleipnir. Like other gods, Loki is a Shapeshifting, shape shifter and in separate sources appears in the form of a salmon, a mare, a Fly (animal), fly, and possibly an elderly woman named Þökk (Old Norse 'thanks'). While sometimes friendly with the gods, Loki engineers the death of the beloved god Baldr. For this, Odin's specially engendered son Váli binds Loki with the entrails of one of his sons, where he writhes in pain. In the ''Prose Edda'', this son, Nar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Core Sample
A core sample is a cylindrical section of (usually) a naturally-occurring substance. Most core samples are obtained by drilling with special drills into the substance, such as sediment or rock, with a hollow steel tube, called a core drill. The hole made for the core sample is called the "core hole". A variety of core samplers exist to sample different media under different conditions; there is continuing development in the technology. In the coring process, the sample is pushed more or less intact into the tube. Removed from the tube in the laboratory, it is inspected and analyzed by different techniques and equipment depending on the type of data desired. Core samples can be taken to test the properties of manmade materials, such as concrete, ceramics, some metals and alloys, especially the softer ones. Core samples can also be taken of living things, including human beings, especially of a person's bones for microscopic examination to help diagnose diseases. Methods The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Ocean
The Arctic Ocean is the smallest and shallowest of the world's five oceanic divisions. It spans an area of approximately and is the coldest of the world's oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, although some oceanographers call it the Arctic Mediterranean Sea. It has also been described as an estuary of the Atlantic Ocean. It is also seen as the northernmost part of the all-encompassing world ocean. The Arctic Ocean includes the North Pole region in the middle of the Northern Hemisphere and extends south to about 60°N. The Arctic Ocean is surrounded by Eurasia and North America, and the borders follow topographic features: the Bering Strait on the Pacific side and the Greenland Scotland Ridge on the Atlantic side. It is mostly covered by sea ice throughout the year and almost completely in winter. The Arctic Ocean's surface temperature and salinity vary seasonally as the ice cover melts and freezes; its salinity is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mohns Ridge
The Mohns Ridge is an ultraslow-spreading segment of the Mid-Atlantic Ridge located to the north of Jan Mayen in the Arctic Ocean. It is bounded to the south by the Jan Mayen fracture zone, and transitions to Knipovich Ridge in the north-east. Geology The ridge started forming 53 My ago, as the Greenland Plate and Eurasian Plate started separating. Four separate axial volcanic ridges have been discovered along Mohns Ridge. Notable features Several active and non-active hydrothermal vent fields have been located along Mohns Ridge. In 2008, a black smoker vent field named Loki's Castle Loki's Castle is a field of five active hydrothermal vents in the Atlantic, mid-Atlantic Ocean, located at 73rd parallel north, 73 degrees north on the Mid-Atlantic Ridge between Iceland and Svalbard at a depth of . When they were discovered in m ... was discovered along one of the axial volcanic ridges in the area. The Schulz Bank seamount is located on the northern part of the ridge, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loki's Castle
Loki's Castle is a field of five active hydrothermal vents in the Atlantic, mid-Atlantic Ocean, located at 73rd parallel north, 73 degrees north on the Mid-Atlantic Ridge between Iceland and Svalbard at a depth of . When they were discovered in mid-July 2008, they were the most northerly black smoker vents known to science. They are of geological interest as they occur in a relatively stable region of the Earth's crust with diminished tectonic forces and consequently fewer hydrothermal vents. They are the site where a biologically distinct class of archaea, the Lokiarchaeota, were discovered. Geography Loki's Castle is located on the Gakkel Ridge (previously the Arctic Mid-Ocean Ridge), where the Mohns and Knipovich ridges converge. Oceanic core complex, Ocean core complexes are found to the northwest. The field resides approximately deep at the boundary of the Greenland Sea, Greenland and Norwegian Sea. History Discovery The vents were discovered in 2008 by a 25-person mult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrothermal Vent
Hydrothermal vents are fissures on the seabed from which geothermally heated water discharges. They are commonly found near volcanically active places, areas where tectonic plates are moving apart at mid-ocean ridges, ocean basins, and hotspots. The dispersal of hydrothermal fluids throughout the global ocean at active vent sites creates hydrothermal plumes. Hydrothermal deposits are rocks and mineral ore deposits formed by the action of hydrothermal vents. Hydrothermal vents exist because the Earth is both geologically active and has large amounts of water on its surface and within its crust. Under the sea, they may form features called black smokers or white smokers, which deliver a wide range of elements to the world's oceans, thus contributing to global marine biogeochemistry. Relative to the majority of the deep sea, the areas around hydrothermal vents are biologically more productive, often hosting complex communities fueled by the chemicals dissolved in the vent fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
