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Thiomargarita
''Thiomargarita'' is a genus (family Thiotrichaceae) which includes the vacuolate sulfur bacteria species ''Thiomargarita namibiensis'', ''Candidatus Thiomargarita nelsonii'', and ''Ca. Thiomargarita joergensii''. In 2022, scientists working in a Caribbean mangrove discovered an extremely large member of the genus, provisionally named '' T. magnifica'', whose cells are easily visible to the naked eye at up to long. Representatives of this genus can be found in a variety of environments that are rich in hydrogen sulfide, including methane seeps, mud volcanoes, brine pools, and organic-rich sediments such as those found beneath the Benguela Current and Humboldt Current. These bacteria are generally considered to be chemolithotrophs that utilize reduced inorganic species of sulfur as metabolic electron donor In chemistry, an electron donor is a chemical entity that donates electrons to another compound. It is a reducing agent that, by virtue of its donating electrons, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiomargarita Namibiensis
''Thiomargarita namibiensis'' is a Gram-negative coccoid bacterium, found in the ocean sediments of the continental shelf of Namibia. It is the second largest bacterium ever discovered, as a rule in diameter, but sometimes attaining . Cells of ''Thiomargarita namibiensis'' are large enough to be visible to the naked eye. Although the species held the record for the largest known bacterium, ''Epulopiscium fishelsoni'' – previously discovered in the gut of surgeonfish – grows slightly longer, but narrower. ''Thiomargarita'' means "sulfur pearl". This refers to the appearance of the cells; they contain microscopic sulfur granules that scatter incident light, lending the cell a pearly lustre. Like many coccoid bacteria such as ''Streptococcus'', their cellular division tends to occur along a single axis, causing their cells to form chains, rather like strings of pearls. The species name ''namibiensis'' means "of Namibia". Occurrence The species was discovered by Heide N. Sch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiomargarita Nelsonii
''Thiomargarita'' is a genus (family Thiotrichaceae) which includes the vacuolate sulfur bacteria species ''Thiomargarita namibiensis'', ''Candidatus Thiomargarita nelsonii'', and ''Ca. Thiomargarita joergensii''. In 2022, scientists working in a Caribbean mangrove discovered an extremely large member of the genus, provisionally named '' T. magnifica'', whose cells are easily visible to the naked eye at up to long. Representatives of this genus can be found in a variety of environments that are rich in hydrogen sulfide, including methane seeps, mud volcanoes, brine pools, and organic-rich sediments such as those found beneath the Benguela Current and Humboldt Current. These bacteria are generally considered to be chemolithotrophs that utilize reduced inorganic species of sulfur as metabolic electron donors to produce energy for the fixation of carbon into biomass. Carbon fixation occurs via the Calvin Benson Bassham cycle and possibly the reverse Krebs cycle The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiomargarita Joergensii
''Thiomargarita'' is a genus (family Thiotrichaceae) which includes the vacuolate sulfur bacteria species ''Thiomargarita namibiensis'', ''Candidatus Thiomargarita nelsonii'', and ''Ca. Thiomargarita joergensii''. In 2022, scientists working in a Caribbean mangrove discovered an extremely large member of the genus, provisionally named '' T. magnifica'', whose cells are easily visible to the naked eye at up to long. Representatives of this genus can be found in a variety of environments that are rich in hydrogen sulfide, including methane seeps, mud volcanoes, brine pools, and organic-rich sediments such as those found beneath the Benguela Current and Humboldt Current. These bacteria are generally considered to be chemolithotrophs that utilize reduced inorganic species of sulfur as metabolic electron donors to produce energy for the fixation of carbon into biomass. Carbon fixation occurs via the Calvin Benson Bassham cycle and possibly the reverse Krebs cycle The r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiomargarita Magnifica
''Thiomargarita magnifica'' is a species of sulfur-oxidizing gammaproteobacteria, found growing underwater on the detached leaves of red mangroves from the Guadeloupe archipelago in the Lesser Antilles. This filament-shaped bacteria is the largest known bacterium, with an average length of 10 mm and some individuals reaching , making the bacteria visible to the naked eye. The bacterium was described in a preprint submitted in February 2022. The bacterium was originally discovered in the early 2010s by Olivier Gros from the University of the French Antilles at Pointe-à-Pitre, but initially it did not attract much attention as Gros thought his find to be a fungus; it took Gros and other researchers five years to determine that it is a bacterium, and a few more years until Jean-Marie Volland, a graduate student working under the supervision of Gros, figured out its unusual properties. ''Thiomargarita'' means "sulfur pearl" in Latin. This refers to the appearance of the cells; they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiotrichales
The Thiotrichales are an order of Pseudomonadota, including '' Thiomargarita magnifica'', the largest known bacterium.George M. Garrity: ''Bergey's Manual of Systematic Bacteriology''. 2. Auflage. Springer, New York, 2005, Volume 2: ''The Proteobacteria, Part B: The Gammaproteobacteria'' They also include certain pathogens, such as ''Francisella tularensis ''Francisella tularensis'' is a pathogenic species of Gram-negative coccobacillus, an aerobic bacterium. It is nonspore-forming, nonmotile, and the causative agent of tularemia, the pneumonic form of which is often lethal without treatment. It ...'' which causes tularemia (rabbit fever). References Gammaproteobacteria {{gammaproteobacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria Described In 1999
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiotrichaceae
The Thiotrichaceae are a family of Pseudomonadota, including ''Thiomargarita namibiensis'', the largest known bacterium.George M. Garrity: ''Bergey's Manual of Systematic Bacteriology''. 2. Auflage. Springer, New York, 2005, Volume 2: ''The Proteobacteria, Part B: The Gammaproteobacteria'' Some species are movable by gliding, ''Thiospira'' by using flagella A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have f .... References External links ThiotrichaceaeJ.P. Euzéby: List of Prokaryotic names with Standing in Nomenclature Thiotrichales {{gammaproteobacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuole
A vacuole () is a membrane-bound organelle which is present in plant and fungal cells and some protist, animal, and bacterial cells. Vacuoles are essentially enclosed compartments which are filled with water containing inorganic and organic molecules including enzymes in solution, though in certain cases they may contain solids which have been engulfed. Vacuoles are formed by the fusion of multiple membrane vesicles and are effectively just larger forms of these. The organelle has no basic shape or size; its structure varies according to the requirements of the cell. Discovery Contractile vacuoles ("stars") were first observed by Spallanzani (1776) in protozoa, although mistaken for respiratory organs. Dujardin (1841) named these "stars" as ''vacuoles''. In 1842, Schleiden applied the term for plant cells, to distinguish the structure with cell sap from the rest of the protoplasm. In 1885, de Vries named the vacuole membrane as tonoplast. Function The function and signifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Compound
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep mantle remain active areas of investigation. Some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, etc.), carbon monoxide, carbon dioxide, carbides, and the following salts of inorganic anions: carbonates, cyanides, cyanates, and thiocyanates. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it does not occur within living things. History Friedrich Wöhler's conversion of ammonium cyanate into urea in 1828 is often cited as the starting point of modern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Krebs Cycle
The reverse Krebs cycle (also known as the reverse tricarboxylic acid cycle, the reverse TCA cycle, or the reverse citric acid cycle, or the reductive tricarboxylic acid cycle, or the reductive TCA cycle) is a sequence of chemical reactions that are used by some bacteria to produce carbon compounds from carbon dioxide and water by the use of energy-rich reducing agents as electron donors. The reaction is the citric acid cycle run in reverse. Where the Krebs cycle takes carbohydrates and oxidizes them to CO2 and water, the reverse cycle takes CO2 and H2O to make carbon compounds. This process is used by some bacteria (such as Aquificota) to synthesize carbon compounds, sometimes using hydrogen, sulfide, or thiosulfate as electron donors. This process can be seen as an alternative to the fixation of inorganic carbon in the reductive pentose phosphate cycle which occurs in a wide variety of microbes and higher organisms. Differences from Krebs cycle In contrast to the oxidative c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light-independent Reactions
The Calvin cycle, light-independent reactions, bio synthetic phase, dark reactions, or photosynthetic carbon reduction (PCR) cycle of photosynthesis is a series of chemical reactions that convert carbon dioxide and hydrogen-carrier compounds into glucose. The Calvin cycle is present in all photosynthetic eukaryotes and also many photosynthetic bacteria. In plants, these reactions occur in the stroma, the fluid-filled region of a chloroplast outside the thylakoid membranes. These reactions take the products ( ATP and NADPH) of light-dependent reactions and perform further chemical processes on them. The Calvin cycle uses the chemical energy of ATP and reducing power of NADPH from the light dependent reactions to produce sugars for the plant to use. These substrates are used in a series of reduction-oxidation reactions to produce sugars in a step-wise process; there is no direct reaction that converts several molecules of to a sugar. There are three phases to the light-independent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
