|
Azetidine-2-carboxylic Acid
Azetidine-2-carboxylic acid (abbreviated Aze) is a plant Non-proteinogenic amino acids, non-protein amino acid homologue of proline with the molecular formula C4H7NO2. Aze is a heterocyclic, 4 membered ring with nitrogen as its heteroatom (an azetidine), and a carboxylic acid group substituted on one of the ring carbon atoms. The main difference between Aze and proline is the ring of Aze has four members and the ring of proline has five. Aze has the ability to act as an analog of proline and can be incorporated into proteins in place of proline. Synthesis Optically inactive Aze was obtained in small yield from the neurotransmitter GABA by α-bromination, followed by removal of hydrogen bromide from the intermediate γ-amino-α-bromobutyric acid and ring closure by treatment with a barium hydroxide solution. An optically active Aze was obtained by treatment of α,γ-diaminobutyric acid dihydrochloride with a mixture of nitrous and hydrochloric acids to yield γ-amino-α-chlorobu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merck Index
''The Merck Index'' is an encyclopedia of chemicals, drugs and biologicals with over 10,000 monograph on single substances or groups of related compounds published online by the Royal Society of Chemistry. History The first edition of the Merck's Index was published in 1889 by the German chemical company Emanuel Merck and was primarily used as a sales catalog for Merck's growing list of chemicals it sold. The American subsidiary was established two years later and continued to publish it. During World War I the US government seized Merck's US operations and made it a separate American "Merck" company that continued to publish the Merck Index. In 2012 the Merck Index was licensed to the Royal Society of Chemistry. An online version of The Merck Index, including historic records and new updates not in the print edition, is commonly available through research libraries. It also includes an appendix with monographs on organic named reactions. The 15th edition was published in A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convallaria Majalis L
''Convallaria'' is a genus of flowering plants. It is usually described as a monotypic genus with the single species ''Convallaria majalis'' (lily-of-the-valley), but now some botanists distinguish up to three species, also including ''Convallaria keiskei ''Convallaria'' is a genus of flowering plants. It is usually described as a monotypic genus with the single species ''Convallaria majalis Lily of the valley (''Convallaria majalis'' (), sometimes written lily-of-the-valley, is a woodland flow ...'' and '' Convallaria montana''. The generic name means valley in Botanical Latin, in reference to the plant's natural geographical habitat.Gledhill D. 1985. ''The Names of Plants''. Cambridge University Press References {{Taxonbar, from=Q134911 Nolinoideae Asparagaceae genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxic Amino Acids
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell ( cytotoxicity) or an organ such as the liver (hepatotoxicity). By extension, the word may be metaphorically used to describe toxic effects on larger and more complex groups, such as the family unit or society at large. Sometimes the word is more or less synonymous with poisoning in everyday usage. A central concept of toxicology is that the effects of a toxicant are dose-dependent; even water can lead to water intoxication when taken in too high a dose, whereas for even a very toxic substance such as snake venom there is a dose below which there is no detectable toxic effect. Toxicity is species-specific, making cross-species analysis problematic. Newer paradigms and metrics are evolving to bypa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azetidines
Azetidine is a saturated heterocyclic organic compound containing three carbon atoms and one nitrogen atom. It is a liquid at room temperature with a strong odor of ammonia and is strongly basic compared to most secondary amines. Synthesis and occurrence Azetidines can be prepared by reduction of azetidinones (β-lactams) with lithium aluminium hydride. Even more effective is a mixture of lithium aluminium hydride and aluminium trichloride Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula . It forms hexahydrate with the formula , containing six water molecules of hydration. Both are colourless crystals, but samples are often conta ..., a source of "AlClH2" and "AlCl2H". Azetidine can also be produced by a multistep route from 3-amino-1-propanol. Regio- and diastereoselective synthesis of 2-arylazetidines could be performed from appropriately substituted oxiranes via ring transformation. It is controlled by Baldwin's Rules ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclic Amino Acids
Cycle, cycles, or cyclic may refer to: Anthropology and social sciences * Cyclic history, a theory of history * Cyclical theory, a theory of American political history associated with Arthur Schlesinger, Sr. * Social cycle, various cycles in social sciences ** Business cycle, the downward and upward movement of gross domestic product (GDP) around its ostensible, long-term growth trend Arts, entertainment, and media Films * ''Cycle'' (2008 film), a Malayalam film * ''Cycle'' (2017 film), a Marathi film Literature * ''Cycle'' (magazine), an American motorcycling enthusiast magazine * Literary cycle, a group of stories focused on common figures Music Musical terminology * Cycle (music), a set of musical pieces that belong together ** Cyclic form, a technique of construction involving multiple sections or movements **Interval cycle, a collection of pitch classes generated from a sequence of the same interval class **Song cycle, individually complete songs designed to be perfo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aminoacyl TRNA Synthetase
An aminoacyl-tRNA synthetase (aaRS or ARS), also called tRNA-ligase, is an enzyme that attaches the appropriate amino acid onto its corresponding tRNA. It does so by catalyzing the transesterification of a specific cognate amino acid or its precursor to one of all its compatible cognate tRNAs to form an aminoacyl-tRNA. In humans, the 20 different types of aa-tRNA are made by the 20 different aminoacyl-tRNA synthetases, one for each amino acid of the genetic code. This is sometimes called "charging" or "loading" the tRNA with an amino acid. Once the tRNA is charged, a ribosome can transfer the amino acid from the tRNA onto a growing peptide, according to the genetic code. Aminoacyl tRNA therefore plays an important role in RNA translation, the expression of genes to create proteins. Mechanism The synthetase first binds ATP and the corresponding amino acid (or its precursor) to form an aminoacyl-adenylate, releasing inorganic pyrophosphate (PPi). The adenylate-aaRS complex th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Folding
Protein folding is the physical process by which a protein chain is translated to its native three-dimensional structure, typically a "folded" conformation by which the protein becomes biologically functional. Via an expeditious and reproducible process, a polypeptide folds into its characteristic three-dimensional structure from a random coil. Each protein exists first as an unfolded polypeptide or random coil after being translated from a sequence of mRNA to a linear chain of amino acids. At this stage the polypeptide lacks any stable (long-lasting) three-dimensional structure (the left hand side of the first figure). As the polypeptide chain is being synthesized by a ribosome, the linear chain begins to fold into its three-dimensional structure. Folding of many proteins begins even during translation of the polypeptide chain. Amino acids interact with each other to produce a well-defined three-dimensional structure, the folded protein (the right hand side of the figure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemoglobin
Hemoglobin (haemoglobin BrE) (from the Greek word αἷμα, ''haîma'' 'blood' + Latin ''globus'' 'ball, sphere' + ''-in'') (), abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein present in red blood cells (erythrocytes) of almost all vertebrates (the exception being the fish family Channichthyidae) as well as the tissues of some invertebrates. Hemoglobin in blood carries oxygen from the respiratory organs (''e.g.'' lungs or gills) to the rest of the body (''i.e.'' tissues). There it releases the oxygen to permit aerobic respiration to provide energy to power functions of an organism in the process called metabolism. A healthy individual human has 12to 20grams of hemoglobin in every 100mL of blood. In mammals, the chromoprotein makes up about 96% of the red blood cells' dry content (by weight), and around 35% of the total content (including water). Hemoglobin has an oxygen-binding capacity of 1.34mL O2 per gram, which increases the total blood oxy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, horns, claws, hooves, and the outer layer of skin among vertebrates. Keratin also protects epithelial cells from damage or stress. Keratin is extremely insoluble in water and organic solvents. Keratin monomers assemble into bundles to form intermediate filaments, which are tough and form strong unmineralized epidermal appendages found in reptiles, birds, amphibians, and mammals. Excessive keratinization participate in fortification of certain tissues such as in horns of cattle and rhinos, and armadillos' osteoderm. The only other biological matter known to approximate the toughness of keratinized tissue is chitin. Keratin comes in two types, the primitive, softer forms found in all vertebrates and harder, derived forms found only among saur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collagen
Collagen () is the main structural protein in the extracellular matrix found in the body's various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whole-body protein content. Collagen consists of amino acids bound together to form a triple helix of elongated fibril known as a collagen helix. It is mostly found in connective tissue such as cartilage, bones, tendons, ligaments, and skin. Depending upon the degree of mineralization, collagen tissues may be rigid (bone) or compliant (tendon) or have a gradient from rigid to compliant (cartilage). Collagen is also abundant in corneas, blood vessels, the gut, intervertebral discs, and the dentin in teeth. In muscle tissue, it serves as a major component of the endomysium. Collagen constitutes one to two percent of muscle tissue and accounts for 6% of the weight of the skeletal muscle tissue. The fibroblast is the most common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fabaceae
The Fabaceae or Leguminosae,International Code of Nomenclature for algae, fungi, and plants. Article 18.5 states: "The following names, of long usage, are treated as validly published: ....Leguminosae (nom. alt.: Fabaceae; type: Faba Mill. Vicia L.; ... When the Papilionaceae are regarded as a family distinct from the remainder of the Leguminosae, the name Papilionaceae is conserved against Leguminosae." English pronunciations are as follows: , and . commonly known as the legume, pea, or bean family, are a large and agriculturally important of |
Polygonatum
''Polygonatum'' , also known as King Solomon's-seal or Solomon's seal, is a genus of flowering plants. In the APG III classification system, it is placed in the family Asparagaceae, subfamily Nolinoideae (formerly the family Ruscaceae). It has also been classified in the former family Convallariaceae and, like many lilioid monocots, was formerly classified in the lily family, Liliaceae. The genus is distributed throughout the temperate Northern Hemisphere. Most of the approximately 63 species occur in Asia, with 20 endemic to China.Wujisguleng, W., et al. (2012)Ethnobotanical review of food uses of ''Polygonatum'' (Convallariaceae) in China.''Acta Societatis Botanicorum Poloniae'' 81(4) 239-44. Etymology ''Polygonatum'' comes from the ancient Greek for "many knees", referring to the multiple jointed rhizome. One explanation for the derivation of the common name "Solomon's seal" is that the roots bear depressions which resemble royal seals. Another is that the cut roots resem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.svg "Click for more on -> Collagen")
