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SAR11
The Pelagibacterales are an order in the Alphaproteobacteria composed of free-living marine bacteria that make up roughly one in three cells at the ocean's surface. Overall, members of the ''Pelagibacterales'' are estimated to make up between a quarter and a half of all prokaryotic cells in the ocean. Initially, this taxon was known solely by metagenomic data and was known as the SAR11 clade. It was first placed in the Rickettsiales, but was later raised to the rank of order, and then placed as sister order to the Rickettsiales in the subclass Rickettsidae. It includes the highly abundant marine species '' Pelagibacter ubique''. Bacteria in this order are unusually small. Due to their small genome size and limited metabolic function, ''Pelagibacterales'' have become a model organism for 'streamlining theory'. ''P. ubique'' and related species are oligotrophs (scavengers) and feed on dissolved organic carbon and nitrogen. They are unable to fix carbon or nitrogen, but can p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagibacter
"''Candidatus'' Pelagibacter", with the single species "''Ca.'' P. communis", was isolated in 2002 and given a specific name, although it has not yet been described as required by the bacteriological code. It is an abundant member of the SAR11 clade in the phylum ''Alphaproteobacteria''. SAR11 members are highly dominant organisms found in both salt and fresh water worldwide and were originally known only from their rRNA genes, first identified in the Sargasso Sea in 1990 by Stephen Giovannoni's laboratory at Oregon State University and later found in oceans worldwide. "''Ca.'' P. communis" and its relatives may be the most abundant organisms in the ocean, and quite possibly the most abundant bacteria in the entire world. It can make up about 25% of all microbial plankton cells, and in the summer they may account for approximately half the cells present in temperate ocean surface water. The total abundance of "''Ca.'' P. communis" and relatives is estimated to be about 2 ×& ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alphaproteobacteria
Alphaproteobacteria is a class of bacteria in the phylum Pseudomonadota (formerly Proteobacteria). The Magnetococcales and Mariprofundales are considered basal or sister to the Alphaproteobacteria. The Alphaproteobacteria are highly diverse and possess few commonalities, but nevertheless share a common ancestor. Like all ''Proteobacteria'', its members are gram-negative and some of its intracellular parasitic members lack peptidoglycan and are consequently gram variable. Characteristics The Alphaproteobacteria are a diverse taxon and comprises several phototrophic genera, several genera metabolising C1-compounds (''e.g.'', ''Methylobacterium'' spp.), symbionts of plants (''e.g.'', '' Rhizobium'' spp.), endosymbionts of arthropods (''Wolbachia'') and intracellular pathogens (''e.g. Rickettsia''). Moreover, the class is sister to the protomitochondrion, the bacterium that was engulfed by the eukaryotic ancestor and gave rise to the mitochondria, which are organelles in eukaryoti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rickettsidae
Alphaproteobacteria is a class of bacteria in the phylum Pseudomonadota (formerly Proteobacteria). The Magnetococcales and Mariprofundales are considered basal or sister to the Alphaproteobacteria. The Alphaproteobacteria are highly diverse and possess few commonalities, but nevertheless share a common ancestor. Like all ''Proteobacteria'', its members are gram-negative and some of its intracellular parasitic members lack peptidoglycan and are consequently gram variable. Characteristics The Alphaproteobacteria are a diverse taxon and comprises several phototrophic genera, several genera metabolising C1-compounds (''e.g.'', ''Methylobacterium'' spp.), symbionts of plants (''e.g.'', '' Rhizobium'' spp.), endosymbionts of arthropods ('' Wolbachia'') and intracellular pathogens (''e.g. Rickettsia''). Moreover, the class is sister to the protomitochondrion, the bacterium that was engulfed by the eukaryotic ancestor and gave rise to the mitochondria, which are organelles in eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streamlining Theory
Genomic streamlining is a theory in evolutionary biology and microbial ecology that suggests that there is a reproductive benefit to prokaryotes having a smaller genome size with less Noncoding DNA, non-coding DNA and fewer non-essential genes. There is a lot of variation in prokaryotic genome size, with the smallest free-living cell's genome being roughly ten times smaller than the largest prokaryote. Two of the bacterial taxa with the smallest genomes are ''Prochlorococcus'' and ''Pelagibacter ubique,'' both highly abundant marine bacteria commonly found in oligotrophic regions. Similar reduced genomes have been found in uncultured marine bacteria, suggesting that genomic streamlining is a common feature of bacterioplankton. This theory is typically used with reference to free-living organisms in oligotrophic environments. Overview Genome streamlining theory states that certain prokaryotic genomes tend to be small in size in comparison to other prokaryotes, and all eukaryotes, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrion
A mitochondrion (; ) is an organelle found in the cells of most Eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857 in the voluntary muscles of insects. The term ''mitochondrion'' was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase coined by Philip Siekevitz in a 1957 article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). A large number of unicellular organisms, such as microsporidia, parabasalids and diplomonads, have reduced or transformed their mitochondria into other structures. One eukaryote, '' Monocercomonoides'', is known to have completely lost its mitochondria, and one multicellular organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagibacteraceae
The Pelagibacteraceae are a family in the Alphaproteobacteria composed of free-living marine bacteria Marine prokaryotes are marine bacteria and marine archaea. They are defined by their habitat as prokaryotes that live in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. All cellula .... References Alphaproteobacteria {{alphaproteobacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Bacteria
Marine prokaryotes are marine bacteria and marine archaea. They are defined by their habitat as prokaryotes that live in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. All cellular life forms can be divided into prokaryotes and eukaryotes. Eukaryotes are organisms whose cells have a nucleus enclosed within membranes, whereas prokaryotes are the organisms that do not have a nucleus enclosed within a membrane. The three-domain system of classifying life adds another division: the prokaryotes are divided into two domains of life, the microscopic bacteria and the microscopic archaea, while everything else, the eukaryotes, become the third domain. Prokaryotes play important roles in ecosystems as decomposers recycling nutrients. Some prokaryotes are pathogenic, causing disease and even death in plants and animals. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proteorhodopsin
Proteorhodopsin (also known as pRhodopsin) is a family of transmembrane proteins that use retinal as a chromophore for light-mediated functionality, in this case, a proton pump. pRhodopsin is found in marine planktonic bacteria, archaea and eukaryotes ( protae), but was first discovered in bacteria. Its name is derived from proteobacteria (now called Pseudomonadota) that were named after Ancient Greek Πρωτεύς (Proteus), an early sea god mentioned by Homer as "Old Man of the Sea", Ῥόδος (rhódon) for "rose", due to its pinkish color, and ὄψις ( opsis) for "sight". Some members of the family, Homologous rhodopsin-like pigments, i.e. bacteriorhodopsin (of which there are more than 800 types) have Sensory Functions like opsins, integral for visual phototransduction. Many of these sensory functions are unknown – for example, the function of Neuropsin in the human retina. Members are known to have different absorption spectra including green and blue visibl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oregon State University
Oregon State University (OSU) is a Public university, public Land-grant university, land-grant, research university in Corvallis, Oregon. OSU offers more than 200 undergraduate-degree programs along with a variety of graduate and doctoral degrees. It has the 10th largest engineering college in the nation for 2022. Undergraduate enrollment for all colleges combined averages close to 32,000, making it the state's largest university. Out-of-state students make up over one-quarter of undergraduates and an additional 5,500 students are engaged in graduate coursework through the university. Since its founding, over 272,000 students have graduated from OSU. It is Carnegie Classification of Institutions of Higher Education, classified among "Doctoral Universities – Very high research activity". Chartered as a land-grant university initially, OSU became one of the four inaugural members of the National Sea Grant College Program, Sea Grant in 1971. It joined the National Space Grant Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Hawaiʻi At Mānoa
The University of Hawaii at Mānoa (University of Hawaii—Mānoa, UH Mānoa, Hawai'i, or simply UH) is a public land-grant research university in Mānoa, a neighborhood in Honolulu, Hawaii. It is the flagship campus of the University of Hawaiʻi system and houses the main offices of the system. Most of the campus occupies the eastern half of the mouth of Mānoa Valley, with the John A. Burns School of Medicine located adjacent to the Kakaʻako Waterfront Park. U.H. offers over 200 degree programs across 17 colleges and schools. It is accredited by the WASC Senior College and University Commission and governed by the Hawaii State Legislature and a semi-autonomous board of regents. It also a member of the Association of Pacific Rim Universities. Mānoa is classified among "R1: Doctoral Universities – Very high research activity". It is a land-grant university that also participates in the sea-grant, space-grant, and sun-grant research consortia; it is one of only four suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Craig A
__NOTOC__ Craig may refer to: Geology * Craig (landform), a rocky hill or mountain often having large casims or sharp intentations. People (and fictional characters) * Craig (surname) *Craig (given name) Places Scotland * Craig, Angus, aka Barony of Craigie United States * Craig, Alaska, a city * Craig, Colorado, a city * Craig, Indiana, an unincorporated place *Craig, Iowa, a city *Craig, Missouri, a city *Craig, Montana Craig is an unincorporated community and census-designated place (CDP) in Lewis and Clark County, Montana, United States. As of the 2010 census, the population was 43. Craig is located along Interstate 15 on the west side of the Missouri River, ..., an unincorporated place * Craig, Nebraska, a village * Craig, Ohio, an unincorporated community * Craig County, Virginia * Craig County, Oklahoma * Craig Township (other) (two places) Other uses * Craig (song) * Craig Electronics, a consumer electronics company * Craig Broadcast Systems, later Craig Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
