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Methylotrophy
Methylotrophs are a diverse group of microorganisms that can use redox, reduced one-carbon compounds, such as methanol or methane, as the carbon source for their growth; and multi-carbon compounds that contain no carbon-carbon bonds, such as dimethyl ether and dimethylamine. This group of microorganisms also includes those capable of assimilating reduced one-carbon compounds by way of carbon dioxide using the ribulose bisphosphate pathway. These organisms should not be confused with methanogens which on the contrary produce methane as a by-product from various one-carbon compounds such as carbon dioxide. Some methylotrophs can degrade the greenhouse gas methane, and in this case they are called methanotrophs. The abundance, purity, and low price of methanol compared to commonly used sugars make methylotrophs competent organisms for production of amino acids, vitamins, recombinant proteins, single-cell proteins, co-enzymes and cytochromes. Metabolism The key intermediate in met ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanotroph
Methanotrophs (sometimes called methanophiles) are prokaryotes that metabolize methane as their source of carbon and chemical energy. They are bacteria or archaea, can grow aerobically or anaerobically, and require single-carbon compounds to survive. Methanotrophs are especially common in or near environments where methane is produced, although some methanotrophs can oxidize atmospheric methane. Their habitats include wetlands, soils, marshes, rice paddies, landfills, aquatic systems (lakes, oceans, streams) and more. They are of special interest to researchers studying global warming, as they play a significant role in the global methane budget, by reducing the amount of methane emitted to the atmosphere. Methanotrophy is a special case of methylotrophy, using single-carbon compounds that are more reduced than carbon dioxide. Some methylotrophs, however, can also make use of multi-carbon compounds; this differentiates them from methanotrophs, which are usually fastidious ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microorganism
A microorganism, or microbe, is an organism of microscopic scale, microscopic size, which may exist in its unicellular organism, single-celled form or as a Colony (biology)#Microbial colonies, colony of cells. The possible existence of unseen microbial life was suspected from antiquity, with an early attestation in Jain literature authored in 6th-century BC India. The scientific study of microorganisms began with their observation under the microscope in the 1670s by Anton van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s, Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera, diphtheria, and anthrax. Microorganisms are extremely diverse, representing most unicellular organisms in all three domains of life: two of the three domains, Archaea and Bacteria, only contain microorganisms. The third domain, Eukaryota, includes all multicellular o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methane Monooxygenase
Methane monooxygenase (MMO) is an enzyme capable of oxidizing the C-H bond in methane as well as other alkanes. Methane monooxygenase belongs to the class of oxidoreductase enzymes (). There are two forms of MMO: the well-studied soluble form (sMMO) and the particulate form (pMMO). The active site in sMMO contains a di-iron center bridged by an oxygen atom (Fe-O-Fe), whereas the active site in pMMO utilizes copper. Structures of both proteins have been determined by X-ray crystallography; however, the location and mechanism of the active site in pMMO is still poorly understood and is an area of active research. The particulate methane monooxygenase and related ammonia monooxygenase are integral membrane proteins, occurring in methanotrophs and ammonia oxidisers, respectively, which are thought to be related. These enzymes have a relatively wide substrate specificity and can catalyse the oxidation of a range of substrates including ammonia, methane, halogenated hydrocarbons, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylamine
Methylamine, also known as methanamine, is an organic compound with a formula of . This colorless gas is a derivative of ammonia, but with one hydrogen atom being replaced by a methyl group. It is the simplest primary amine. Methylamine is sold as a solution in methanol, ethanol, tetrahydrofuran, or water, or as the anhydrous gas in pressurized metal containers. Industrially, methylamine is transported in its anhydrous form in pressurized railcars and tank trailers. It has a strong odor similar to rotten fish. Methylamine is used as a building block for the synthesis of numerous other commercially available compounds. Industrial production Methylamine has been produced industrially since the 1920s (originally by Commercial Solvents Corporation for dehairing of animal skins). This was made possible by and his wife Eugenia who discovered amination of alcohols, including methanol, on alumina or kaolin catalyst after WWI, filed two patent applications in 1919 and published an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimethylamine N-oxide
Trimethylamine ''N''-oxide (TMAO) is an organic compound with the formula . It is in the class of amine oxides. Although the anhydrous compound is known, trimethylamine ''N''-oxide is usually encountered as the dihydrate. Both the anhydrous and hydrated materials are white, water-soluble solids. TMAO is found in the tissues of marine crustaceans and marine fish, where it prevents water pressure from distorting proteins and thus killing the animal. The concentration of TMAO increases with the depth at which the animal lives; TMAO is found in high concentrations in the deepest-living described fish species, '' Pseudoliparis swirei'', which was found in the Mariana Trench, at a recorded depth of . In animals, TMAO is a product of the oxidation of trimethylamine, a common metabolite of trimethyl quaternary ammonium compounds, like choline, trimethylglycine, and L-carnitine. High TMAO concentrations are associated with an increased risk of all-cause mortality and cardiovascular di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanol
Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical compound and the simplest aliphatic Alcohol (chemistry), alcohol, with the chemical formula (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a light, Volatility (chemistry), volatile, colorless and flammable liquid with a distinctive alcoholic odor similar to that of ethanol (potable alcohol), but is more acutely toxic than the latter. Methanol acquired the name wood alcohol because it was once produced through destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide. Methanol consists of a methyl group linked to a polar hydroxyl group. With more than 20 million tons produced annually, it is used as a Precursor (chemistry), precursor to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, methyl ''tert''-butyl ether, methyl benzoate, anisole, peroxyacids, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimethylamine
Trimethylamine (TMA) is an organic compound with the formula N(CH3)3. It is a trimethylated derivative of ammonia. TMA is widely used in industry. At higher concentrations it has an ammonia-like odor, and can cause necrosis of mucous membranes on contact. At lower concentrations, it has a "fishy" odor, the odor associated with rotting fish. Physical and chemical properties TMA is a colorless, hygroscopic, and flammable tertiary amine. It is a gas at room temperature but is usually sold as a 40% solution in water. It is also sold in pressurized gas cylinders. TMA protonates to give the trimethylammonium cation. Trimethylamine is a good nucleophile, and this reactivity underpins most of its applications. Trimethylamine is a Lewis base that forms adducts with a variety of Lewis acids. Production Industry and laboratory Trimethylamine is prepared by the reaction of ammonia and methanol employing a catalyst: :3 CH3OH + NH3 → (CH3)3N + 3 H2O This reaction coproduces the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it is difficult because it is a gas at standard temperature and pressure. In the Earth's atmosphere methane is transparent to visible light but absorbs infrared radiation, acting as a greenhouse gas. Methane is an Organic chemistry, organic Organic compound, compound, and among the simplest of organic compounds. Methane is also a hydrocarbon. Naturally occurring methane is found both below ground and under the seafloor and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the Atmosphere of Earth, atmosphere, it is known as atmospheric methane. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetramethylammonium
Tetramethylammonium (TMA) is the simplest quaternary ammonium cation. It has the chemical formula and consists of four methyl groups (, denoted Me) attached to a central nitrogen atom. The cation is isoelectronic with neopentane (). It is positively-charged and can only be isolated in association with a counter-ion. Common salts include tetramethylammonium chloride and tetramethylammonium hydroxide. Tetramethylammonium salts are used in chemical synthesis and in pharmacological research. It confers no color to its salts. Common nomenclature In the toxicological literature, ''naturally occurring'' tetramethylammonium (anion unspecified) is often referred to by the name "tetramine". Unfortunately, this non-systematic or "trivial" name is also used for other chemical entities, including a toxic rodenticide ( Tetramethylenedisulfotetramine). Similarly, the acronym "TMA", which is frequently used for tetramethylammonium in the pharmacological literature, may also refer to the inve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formic Acid
Formic acid (), systematically named methanoic acid, is the simplest carboxylic acid. It has the chemical formula HCOOH and structure . This acid is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Esters, salts, and the anion derived from formic acid are called formates. Industrially, formic acid is produced from methanol. Natural occurrence Formic acid, which has a pungent, penetrating odor, is found naturally in insects, weeds, fruits and vegetables, and forest emissions. It appears in most ants and in stingless bees of the genus '' Oxytrigona''. Wood ants from the genus ''Formica'' can spray formic acid on their prey or to defend the nest. The puss moth caterpillar (''Cerura vinula'') will spray it as well when threatened by predators. It is also found in the trichomes of stinging nettle (''Urtica dioica''). Apart from that, this acid is incorporated in many fruits such as pineapple (0.21 mg per 100 g), apple (2 mg per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethyl Sulfide
Dimethyl sulfide (DMS) or methylthiomethane is an organosulfur compound with the formula . It is the simplest thioether and has a characteristic disagreeable odor. It is a flammable liquid that boils at . It is a component of the smell produced from cooking of certain vegetables (notably maize, cabbage, and beetroot) and seafoods. It is also an indication of bacterial contamination in malt production and brewing. It is a breakdown product of dimethylsulfoniopropionate (DMSP), and is also produced by the bacterial metabolism of methanethiol. Occurrence and production DMS originates primarily from DMSP, a major secondary metabolite in some marine algae. DMS is the most abundant biological sulfur compound emitted to the atmosphere. Emission occurs over the oceans by phytoplankton. DMS is also produced naturally by bacterial transformation of dimethyl sulfoxide (DMSO) waste that is disposed of into sewers, where it can cause environmental odor problems. DMS is oxidized in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formamide
Formamide is an amide derived from formic acid. It is a colorless liquid which is miscible with water and has an ammonia-like odor. It is chemical feedstock for the manufacture of sulfa drugs and other pharmaceuticals, herbicides and pesticides, and in the manufacture of hydrocyanic acid. It has been used as a softener for paper and fiber. It is a solvent for many ionic compounds. It has also been used as a solvent for resins and plasticizers. Some astrobiologists suggest that it may be an alternative to water as the main solvent in other forms of life. Formamides are compounds of the type RR′NCHO. One important formamide is dimethylformamide, (CH3)2NCHO. Production Historical production In the past, formamide was produced by treating formic acid with ammonia, which produces ammonium formate, which in turn yields formamide upon heating: : HCOOH + NH3 → : → HCONH2 + H2O Formamide is also generated by aminolysis of ethyl formate: :HCOOCH2CH3 + NH3 → HCONH2 + CH3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
