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Selenoneine
Selenoneine is a selenium containing ergothioneine derivative where the selenium (Se) atom replaces a sulfur atom. It can be systematically named as (2-selenyl-Nα,Nα,Nα-trimethyl-L-histidine or 3-(2-hydroseleno-1H-imidazol-5-yl)-2-(trimethylammonio)propanoate). It is found in the blood of bluefin tuna, and other sea dwelling animals like turtles, mackerel, beluga, and giant petrels. It is an antioxidant, combining with reactive oxygen species and boosting the action of GPx1. Selenoneine is produced by microorganisms using enzymes that form a selenium-carbon bond. Humans that eat fish have selenoneine in their blood. About half of selenium is in the form of selenoneine. Selenoneine inhibits angiotensin-converting enzyme. In vertebrates, selenoneine is transported into cells using OCTN1. Selenoneine reacts with methyl mercury to form a mercury tetraselenoate complex, which degrades to tiemannite, a mercury selenide Mercury selenide (HgSe; sometimes mercury(II) selenide) is a che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenium
Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. It seldom occurs in its elemental state or as pure ore compounds in the Earth's crust. Selenium – from Greek ( 'Moon') – was discovered in 1817 by , who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). Selenium is found in metal sulfide ores, where it partially replaces the sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores, most often during production. Minerals that are pure selenide or selenate compounds are known but rare. The chief commercial uses for selenium today are glassmaking and pigments. Selenium is a semiconductor and is used in photocells. Applications in electronics, once important, have been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ergothioneine
Ergothioneine is a naturally occurring amino acid and is a thiourea derivative of histidine, containing a sulfur atom on the imidazole ring. This compound occurs in relatively few organisms, notably actinomycetota, cyanobacteria, and certain fungi. Ergothioneine was discovered in 1909 and named after the ergot fungus from which it was first purified, with its structure being determined in 1911. In humans, ergothioneine is acquired exclusively through the diet and accumulates in erythrocytes, bone marrow, liver, kidney, seminal fluid, and eyes. Although the effect of ergothioneine ''in vivo'' is under preliminary research, its physiological role in humans is unknown. Ergothioneine is sold as a dietary supplement. Metabolism and sources Ergothioneine has been found in bacteria, plants, and animals, sometimes at millimolar levels. Foods found to contain ergothioneine include liver, kidney, black beans, kidney bean, and oat bran, with the highest levels in bolete and oyster m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ergothioneine
Ergothioneine is a naturally occurring amino acid and is a thiourea derivative of histidine, containing a sulfur atom on the imidazole ring. This compound occurs in relatively few organisms, notably actinomycetota, cyanobacteria, and certain fungi. Ergothioneine was discovered in 1909 and named after the ergot fungus from which it was first purified, with its structure being determined in 1911. In humans, ergothioneine is acquired exclusively through the diet and accumulates in erythrocytes, bone marrow, liver, kidney, seminal fluid, and eyes. Although the effect of ergothioneine ''in vivo'' is under preliminary research, its physiological role in humans is unknown. Ergothioneine is sold as a dietary supplement. Metabolism and sources Ergothioneine has been found in bacteria, plants, and animals, sometimes at millimolar levels. Foods found to contain ergothioneine include liver, kidney, black beans, kidney bean, and oat bran, with the highest levels in bolete and oyster m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenocysteine
Selenocysteine (symbol Sec or U, in older publications also as Se-Cys) is the 21st proteinogenic amino acid. Selenoproteins contain selenocysteine residues. Selenocysteine is an analogue of the more common cysteine with selenium in place of the sulfur. Selenocysteine is present in several enzymes (for example glutathione peroxidases, tetraiodothyronine 5′ deiodinases, thioredoxin reductases, formate dehydrogenases, glycine reductases, selenophosphate synthetase 2, methionine-''R''-sulfoxide reductase B1 (SEPX1), and some hydrogenases). It occurs in all three domains of life, including important enzymes (listed above) present in humans. Selenocysteine was discovered by biochemist Thressa Stadtman at the National Institutes of Health. Chemistry Selenocysteine is the Se-analogue of cysteine. It is rarely encountered outside of living tissue (and is not available commercially) because it is very susceptible to air-oxidation. More common is the oxidized derivative selenocystine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Mercury
Methylmercury (sometimes methyl mercury) is an organometallic cation with the formula . It is the simplest organomercury compound. Methylmercury is extremely toxic, and its derivatives are the major source of organic mercury for humans. It is a bioaccumulative environmental toxicant. Structure and chemistry "Methylmercury" is a shorthand for the hypothetical "methylmercury cation", sometimes written "''methylmercury(1+) cation''" or "''methylmercury(II) cation''". This functional group is composed of a methyl group bonded to an atom of mercury. Its chemical formula is (sometimes written as ).The Methylmercury compound has an overall charge of +1, with Hg in the +2 oxidation state.Methylmercury exists as a substituent in many complexes of the type (L = Lewis base) and MeHgX (X = anion). As a positively charged ion it readily combines with anions such as chloride (), hydroxide () and nitrate (). It has particular affinity for sulfur-containing anions, particularly thiols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Ammonium Compounds
In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged, independent of the pH of their solution. Quaternary ammonium salts or quaternary ammonium compounds (called quaternary amines in oilfield parlance) are salts of quaternary ammonium cations. Polyquats are a variety of engineered polymer forms which provide multiple quat molecules within a larger molecule. Quats are used in consumer applications including as antimicrobials (such as detergents and disinfectants), fabric softeners, and hair conditioners. As an antimicrobial, they are able to inactivate enveloped viruses (such as SARS-CoV-2). Quats tend to be gentler on surfaces than bleach-based disinfectants, and are generally fabric-safe. Synthesis Quaternary ammonium compou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diselenide Bond
Diselenide may refer to: *Diselane, H-Se-Se-H *Carbon diselenide, CSe2, a yellow-orange oily liquid with pungent odor * Any organic chemical compound with a selenium-selenium bond, R-Se-Se-R **Diphenyl diselenide, (C6H5)–Se–Se–(C6H5) *Metal dichalcogenides **Manganese diselenide (MnSe2) **Molybdenum diselenide (MoSe2) **Tungsten diselenide Tungsten diselenide is an inorganic compound with the formula WSe2. The compound adopts a hexagonal crystalline structure similar to molybdenum disulfide. Every tungsten atom is covalently bonded to six selenium ligands in a trigonal prismatic co ... (WSe2) ** Titanium diselenide (TiSe2) {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury Selenide
Mercury selenide (HgSe; sometimes mercury(II) selenide) is a chemical compound of mercury and selenium. It is a grey-black crystalline solid semi-metal with a sphalerite structure. The lattice constant is 0.608 nm. HgSe occurs naturally as the mineral Tiemannite, and is a component of the "intimate mixture" of HgSe and Se known as HgSe2. Along with other II-VI compounds, colloidal nanocrystals of HgSe can be formed. Applications * Selenium is used in filters in some steel plants to remove mercury from exhaust gases. The solid product formed is HgSe. * HgSe can be used as an ohmic contact to wide-gap II-VI semiconductors such as zinc selenide or zinc oxide. Toxicity HgSe is non-toxic as long as it is not ingested due to its insolubility. Toxic hydrogen selenide fumes can be evolved on exposure to acids. HgSe is a relatively stable compound which might mean that it is less toxic than elemental mercury or many organometallic mercury compounds. Selenium's ability to comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tiemannite
Tiemannite is a mineral, mercury selenide, formula HgSe. It occurs in hydrothermal veins associated with other selenides, or other mercury minerals such as cinnabar, and often with calcite. Discovered in 1855 in Germany, it is named after Johann Carl Wilhelm Tiemann (1848–1899). See also *List of minerals *List of minerals named after people This is a list of minerals named after people. The chemical composition follows name. A * Abelsonite: C31H32N4Ni – American physicist Philip Hauge Abelson (1913–2004)alfred *Abswurmbachite: Cu2+Mn3+6O8SiO4 – German mineralogist I ... References * Tiemannite from a micro-disseminated gold deposit in Qiongmo, Liu Jiajun, Zheng Minghua, Liu Jianming, Lu Wenquan, Journal of Chengdu Institute of Technology, vol. 23 (2), pages 21–28 (1996) * Timanite and onofrite in ores of Siberian mercury deposits, Vasil'yev V.I., Lavrent'yev Y.G., Doklady (Academy of Sciences of the USSR, Earth Sciences Section) vol. 222, Pages 159-162 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GPx1
Glutathione peroxidase 1, also known as GPx1, is an enzyme that in humans is encoded by the ''GPX1'' gene on chromosome 3. This gene encodes a member of the glutathione peroxidase family. Glutathione peroxidase functions in the detoxification of hydrogen peroxide, and is one of the most important antioxidant enzymes in humans. Structure This gene encodes a member of the glutathione peroxidase family, consisting of eight known glutathione peroxidases (GPx1-8) in humans. Mammalian Gpx1 (this gene), Gpx2, Gpx3, and Gpx4 have been shown to be selenium-containing enzymes, whereas Gpx6 is a selenoprotein in humans with cysteine-containing homologues in rodents. In selenoproteins, the 21st amino acid selenocysteine is inserted in the nascent polypeptide chain during the process of translational recoding of the UGA stop codon. In addition to the UGA-codon, a cis-acting element in the mRNA, called SECIS, binds SBP2 to recruit other proteins, such as eukaryotic elongation factor selenocys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OCTN1
Solute carrier family 22, member 4, also known as SLC22A4, is a human gene; the encoded protein is known as the ergothioneine transporter. Function The encoded protein is an integral protein of the plasma membrane containing 12 transmembrane segments. The first functional designation of this protein was OCTN1 ("organic cation transporter, novel, type 1"), but efficiency of transport for organic cations (e.g., tetraethylammonium) is very low. The transport efficiency for carnitine is also negligible. Instead, the protein is responsible for the cotransport of sodium ions and ergothioneine, which is an antioxidant, into cells. Thus, a more appropriate functional designation is ETT ("ergothioneine transporter"). Interactions SLC22A4 has been shown to Protein-protein interaction, interact with PDZK1. See also * Solute carrier family References Further reading * * * * * * * * * * * * * * * Solute carrier family {{membrane-protein-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
