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Magnetospirillum Magnetotacticum
''Magnetospirillum'' is a Gram-negative, microaerophilic genus of magnetotactic bacterium, first isolated from pond water by the microbiologist R. P. Blakemore in 1975. They have a spiral (helical) shape and are propelled by a polar flagellum at each end of their cells. Four species have been described: ''M. magnetotacticum'' strain MS-1 (originally classified as ''Aquaspirillum magnetotacticum''; ''M. magneticum'' strain AMB-1; ''M. gryphiswaldense'' and ''M. bellicus''. Habitat The typical habitat of ''Magnetospirillum'' species consists of shallow fresh water and sediments, characterized by low concentrations of oxygen for growth (microaerophilic) where they live in the upper portion of the sediment (oxic/anoxic interface) and prefer an oxygen gradient of around 1–3%. Magnetotaxis Probably the most peculiar characteristic of ''Magnetospirillum'' species is their capacity to orient themselves according to Earth's magnetic field, magnetotaxis. This is achieved through 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 International Code of Nomenclature of Prokaryotes (ICNP) formerly the International Code of Nomenclature of Bacteria (ICNB) or Bacteriological Code (BC) governs the scientific names for Bacteria and Archaea.P. H. A. Sneath, 2003. A short hist .... 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. References External links List of Prokaryotic names with Standing in Nomenclature [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytoplasm
In cell biology, the cytoplasm is all of the material within a eukaryotic cell, enclosed by the cell membrane, except for the cell nucleus. The material inside the nucleus and contained within the nuclear membrane is termed the nucleoplasm. The main components of the cytoplasm are cytosol (a gel-like substance), the organelles (the cell's internal sub-structures), and various cytoplasmic inclusions. The cytoplasm is about 80% water and is usually colorless. The submicroscopic ground cell substance or cytoplasmic matrix which remains after exclusion of the cell organelles and particles is groundplasm. It is the hyaloplasm of light microscopy, a highly complex, polyphasic system in which all resolvable cytoplasmic elements are suspended, including the larger organelles such as the ribosomes, mitochondria, the plant plastids, lipid droplets, and vacuoles. Most cellular activities take place within the cytoplasm, such as many metabolic pathways including glycolysis, and proces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhodospirillales
The Rhodospirillales are an order of Pseudomonadota. Notable Families The ''Acetobacteraceae'' comprise the acetic acid bacteria, which are heterotrophic and produce acetic acid during their respiration.Garrity, George M.; Brenner, Don J.; Krieg, Noel R.; Staley, James T. (eds.) (2005). Bergey's Manual of Systematic Bacteriology, Volume Two: The Proteobacteria, Part C: The Alpha-, Beta-, Delta-, and Epsilonproteobacteria. New York, New York: Springer. . The '' Rhodospirillaceae'' include mainly purple nonsulfur bacteria, which produce energy through photosynthesis. Phylogeny The currently accepted taxonomy is based on the 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 ... (LPSN). The phylogeny is based on whole-genome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemoheterotrophs
A Chemotroph is an organism that obtains energy by the oxidation of electron donors in their environments. These molecules can be organic ( chemoorganotrophs) or inorganic (chemolithotrophs). The chemotroph designation is in contrast to phototrophs, which use photons. Chemotrophs can be either autotrophic or heterotrophic. Chemotrophs can be found in areas where electron donors are present in high concentration, for instance around hydrothermal vents. Chemoautotroph Chemoautotrophs, in addition to deriving energy from chemical reactions, synthesize all necessary organic compounds from carbon dioxide. Chemoautotrophs can use inorganic energy sources such as hydrogen sulfide, elemental sulfur, ferrous iron, molecular hydrogen, and ammonia or organic sources to produce energy. Most chemoautotrophs are extremophiles, bacteria or archaea that live in hostile environments (such as deep sea vents) and are the primary producers in such ecosystems. Chemoautotrophs generally fall into se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microaerobic
A microaerophile is a microorganism that requires environments containing lower levels of dioxygen than that are present in the atmosphere (i.e. < 21% O2; typically 2–10% O2) for optimal growth. A more restrictive interpretation requires the microorganism to be obligate in this requirement. Many microaerophiles are also capnophiles, requiring an elevated concentration of (e.g. 10% CO2 in the case of '' Campylobacter'' ). The original definiti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LPSN
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 International Code of Nomenclature of Prokaryotes (ICNP) formerly the International Code of Nomenclature of Bacteria (ICNB) or Bacteriological Code (BC) governs the scientific names for Bacteria and Archaea.P. H. A. Sneath, 2003. A short hist .... 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. References External links List of Prokaryotic names with Standing in Nomenclature [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single Domain (magnetic)
Single domain, in magnetism, refers to the state of a ferromagnet in which the magnetization does not vary across the magnet. A magnetic particle that stays in a single domain state for all magnetic fields is called a single domain particle (but other definitions are possible; see below). Such particles are very small (generally below a micrometre in diameter). They are also very important in a lot of applications because they have a high coercivity. They are the main source of hardness in hard magnets, the carriers of magnetic storage in tape drives, and the best recorders of the ancient Earth's magnetic field (see paleomagnetism). History Early theories of magnetization in ferromagnets assumed that ferromagnets are divided into magnetic domains and that the magnetization changed by the movement of Domain wall (magnetism), domain walls. However, as early as 1930, Frenkel and Dorfman predicted that sufficiently small particles could only hold one domain, although they greatly over ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetite
Magnetite is a mineral and one of the main iron ores, with the chemical formula Fe2+Fe3+2O4. It is one of the oxides of iron, and is ferrimagnetic; it is attracted to a magnet and can be magnetized to become a permanent magnet itself. With the exception of extremely rare native iron deposits, it is the most magnetic of all the naturally occurring minerals on Earth. Naturally magnetized pieces of magnetite, called lodestone, will attract small pieces of iron, which is how ancient peoples first discovered the property of magnetism. Magnetite is black or brownish-black with a metallic luster, has a Mohs hardness of 5–6 and leaves a black streak. Small grains of magnetite are very common in igneous and metamorphic rocks. The chemical IUPAC name is iron(II,III) oxide and the common chemical name is ''ferrous-ferric oxide''. Properties In addition to igneous rocks, magnetite also occurs in sedimentary rocks, including banded iron formations and in lake and marine sediments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerotaxis
Aerotaxis is the movement caused by oxygen gradients. Positive aerotaxis involves the movement toward higher concentration of environmental oxygen, while negative aerotaxis involves the movement towards a lower concentration of environmental oxygen . Aerotactic bacteria gather around sources of air forming aerotactic bands. Discovery The discovery of aerotaxis was first reported by Theodore Wilhelm Engelmann, as he showed microaerophilic ''Spirillum tenue'' were attracted by low oxygen concentrations. Ten decades after the first discovery of this movement, it was observed that bacteria are actually bound to areas with optimal oxygen concentrations; resulting in the formation of bands. It was concluded that the creations of these bands was largely in part to Oxygen's important role in metabolic pathways as they allowed for surveying aerotaxis in many bacterial species. This ability proves to be important for survival as efficient metabolism directly relates to growth. Aerotaxis not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetosome
Magnetosomes are membranous structures present in magnetotactic bacteria (MTB). They contain iron-rich magnetic particles that are enclosed within a lipid bilayer membrane. Each magnetosome can often contain 15 to 20 magnetite crystals that form a chain which acts like a compass needle to orient magnetotactic bacteria in geomagnetic fields, thereby simplifying their search for their preferred microaerophilic environments. Recent research has shown that magnetosomes are invaginations of the inner membrane and not freestanding vesicles. Magnetite-bearing magnetosomes have also been found in eukaryotic magnetotactic algae, with each cell containing several thousand crystals. Overall, magnetosome crystals have high chemical purity, narrow size ranges, species-specific crystal morphologies and exhibit specific arrangements within the cell. These features indicate that the formation of magnetosomes is under precise biological control and is mediated biomineralization. Magnetotactic bac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organelles
In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. The name ''organelle'' comes from the idea that these structures are parts of cells, as organs are to the body, hence ''organelle,'' the suffix ''-elle'' being a diminutive. Organelles are either separately enclosed within their own lipid bilayers (also called membrane-bound organelles) or are spatially distinct functional units without a surrounding lipid bilayer (non-membrane bound organelles). Although most organelles are functional units within cells, some function units that extend outside of cells are often termed organelles, such as cilia, the flagellum and archaellum, and the trichocyst. Organelles are identified by microscopy, and can also be purified by cell fractionation. There are many types of organelles, particularly in eukaryotic cells. They include structures that make up the endomembrane system (such as the nuclear envelope, endoplasmic reticulum, and Golg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetotaxis
Magnetotaxis is a process implemented by a diverse group of Gram-negative bacteria that involves orienting and coordinating movement in response to Earth's magnetic field. This process is mainly carried out by microaerophilic and anaerobic bacteria found in aquatic environments such as salt marshes, seawater, and freshwater lakes. By sensing the magnetic field, the bacteria are able to orient themselves towards environments with more favorable oxygen concentrations. This orientation towards more favorable oxygen concentrations allows the bacteria to reach these environments faster as opposed to random movement through Brownian motion. Overview Magnetic bacteria (e.g. ''Magnetospirillum magnetotacticum'') contain internal structures known as magnetosomes which are responsible for the process of magnetotaxis. After orienting to the magnetic field using the magnetosomes, the bacteria use flagella to swim along the magnetic field, towards the more favorable environment. Magnetotaxis h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
