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Dipeptides
A dipeptide is an organic compound derived from two amino acids. The constituent amino acids can be the same or different. When different, two isomers of the dipeptide are possible, depending on the sequence. Several dipeptides are physiologically important, and some are both physiologically and commercially significant. A well known dipeptide is aspartame, an artificial sweetener. Dipeptides are white solids. Many are far more water-soluble than the parent amino acids. For example, the dipeptide Ala-Gln has the solubility of 586 g/L more than 10x the solubility of Gln (35 g/L). Dipeptides also can exhibit different stabilities, e.g. with respect to hydrolysis. Gln does not withstand sterilization procedures, whereas this dipeptide does. Because dipeptides are prone to hydrolysis, the high solubility is exploited in infusions, i.e. to provide nutrition. Examples Commercial value About six dipeptides are of commercial interest. *Aspartame (''N''-L-α-aspartyl-L-phenyla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudoproline
Pseudoproline (also pseudo-proline, ψ-Pro) derivatives are artificially created dipeptides to minimize aggregation during Fmoc solid-phase synthesis of peptides. History The chemical synthesis of large peptides is still limited by problems of low solvation during solid phase peptide synthesis (SPPS) or limited solubility of fully protected peptide fragments: even chemoselective ligation methods are hampered by self-association of unprotected peptide blocks. The elucidation of the relationship between preferred conformation of a growing peptide chain and its physicochemical properties reveals that β-sheet (beta-sheet) formation is often paralleled by significant decrease in solvation and solubility. Besides attempts to increase the solvation of peptides by external factors, few attempts, i.e. N-substituted Hmb amino acid derivatives and pseudoprolines (see figure on the top right) have been reported to modify the intrinsic properties of peptides responsible for aggregation and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspartame
Aspartame is an artificial non- saccharide sweetener 200 times sweeter than sucrose and is commonly used as a sugar substitute in foods and beverages. It is a methyl ester of the aspartic acid/phenylalanine dipeptide with the trade names ''NutraSweet'', ''Equal'', and ''Canderel''. First submitted for approval as a food ingredient in 1974, aspartame was approved by the US Food and Drug Administration (FDA) in 1981. Aspartame is one of the most rigorously tested food ingredients. Reviews by over 100 governmental regulatory bodies found the ingredient safe for consumption at current levels.Food Standards Australia New Zealand: , several reviews of clinical trials showed that using aspartame in place of sugar reduces calorie intake and body weight in adults and children. Uses Aspartame is around 180 to 200 times sweeter than sucrose (table sugar). Due to this property, even though aspartame produces of energy per gram when metabolized, the quantity of asparta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspartame
Aspartame is an artificial non- saccharide sweetener 200 times sweeter than sucrose and is commonly used as a sugar substitute in foods and beverages. It is a methyl ester of the aspartic acid/phenylalanine dipeptide with the trade names ''NutraSweet'', ''Equal'', and ''Canderel''. First submitted for approval as a food ingredient in 1974, aspartame was approved by the US Food and Drug Administration (FDA) in 1981. Aspartame is one of the most rigorously tested food ingredients. Reviews by over 100 governmental regulatory bodies found the ingredient safe for consumption at current levels.Food Standards Australia New Zealand: , several reviews of clinical trials showed that using aspartame in place of sugar reduces calorie intake and body weight in adults and children. Uses Aspartame is around 180 to 200 times sweeter than sucrose (table sugar). Due to this property, even though aspartame produces of energy per gram when metabolized, the quantity of asparta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemotactic Peptide
''N''-Formylmethionyl-leucyl-phenylalanine (fMLF, fMLP or ''N''-formyl-met-leu-phe) is an ''N''- formylated tripeptide and sometimes simply referred to as chemotactic peptide is a potent polymorphonuclear leukocyte (PMN) chemotactic factor and is also a macrophage activator. fMLF is the prototypical representative of the ''N''-formylated oligopeptide family of chemotactic factors. These oligopeptides are known to be, or mimic the actions of, the ''N''-formyl oligopeptides that are (a) released by tissue bacteria, (b) attract and activate circulating blood leukocytes by binding to specific G protein coupled receptors on these cells, and (c) thereby direct the inflammatory response to sites of bacterial invasion. fMLF is involved in the innate immunity mechanism for host defense against pathogens. fMLF led to the first discovery of a leukocyte receptor for a chemotactic factor, defined three different types of fMLF receptors that have complementary and/or opposing effects on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ala-Gln
Alanyl-glutamine is a chemical compound which in the form L-alanyl-L-glutamine is used in dietary supplementation, in parenteral nutrition, and in cell culture. It is a dipeptide consisting of alanine and glutamine. Dieterary supplement As a dietary supplement, alanyl-glutamine protects the gastrointestinal tract. The protective effect reduces bacterial translocation, thus reducing the risk of infections and infection-related problems such as diarrhea, dehydration, malabsorption, and electrolyte imbalance. Parenteral nutrition At room temperature with 1 atmosphere of pressure, L-alanyl-L-glutamine has a solubility of about 586 g/L, which is more than 10 times glutamine's solubility (35 g/L). Also, glutamine does not withstand sterilization procedures, whereas alanyl-glutamine does. Alanyl-glutamine's high solubility makes it valuable in parenteral nutrition. Cell culture In cell culture, L-alanyl-L-glutamine is sometimes used as a replacement for L-glutamine because th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Liv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slime Mold
Slime mold or slime mould is an informal name given to several kinds of unrelated eukaryotic organisms with a life cycle that includes a free-living single-celled stage and the formation of spores. Spores are often produced in macroscopic multicellular or multinucleate fruiting bodies which may be formed through aggregation or fusion. Slime molds were formerly classified as fungi but are no longer considered part of that kingdom (biology), kingdom. Although not forming a single Clade, monophyletic clade, they are grouped within the paraphyly, paraphyletic group Protists, Protista. More than 900 species of slime mold occur globally. Their common name refers to part of some of these organisms' life cycles where they can appear as gelatinous "slime". This is mostly seen with the Myxogastria, which are the only Macroscopic scale, macroscopic slime molds. Most slime molds are smaller than a few centimetres, but some species may reach sizes up to several square metres and masses up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chicken
The chicken (''Gallus gallus domesticus'') is a domesticated junglefowl species, with attributes of wild species such as the grey and the Ceylon junglefowl that are originally from Southeastern Asia. Rooster or cock is a term for an adult male bird, and a younger male may be called a cockerel. A male that has been castrated is a capon. An adult female bird is called a hen and a sexually immature female is called a pullet. Humans now keep chickens primarily as a source of food (consuming both their meat and eggs) and as pets. Traditionally they were also bred for cockfighting, which is still practiced in some places. Chickens are one of the most common and widespread domestic animals, with a total population of 23.7 billion , up from more than 19 billion in 2011. There are more chickens in the world than any other bird. There are numerous cultural references to chickens – in myth, folklore and religion, and in language and literature. Genetic studies have poi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclic Peptide
Cyclic peptides are polypeptide chains which contain a circular sequence of bonds. This can be through a connection between the amino and carboxyl ends of the peptide, for example in cyclosporin; a connection between the amino end and a side chain, for example in bacitracin; the carboxyl end and a side chain, for example in colistin; or two side chains or more complicated arrangements, for example in amanitin. Many cyclic peptides have been discovered in nature and many others have been synthesized in the laboratory. Their length ranges from just two amino acid residues to hundreds. In nature they are frequently antimicrobial or toxic; in medicine they have various applications, for example as antibiotics and immunosuppressive agents. Thin-Layer Chromatography (TLC) is a convenient method to detect cyclic peptides in crude extract from bio-mass. Classification Cyclic peptides can be classified according to the types of bonds that comprise the ring. *Homodetic cyclic peptides, su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polysphondylium Violaceum
''Polysphondylium'' is a genus of cellular slime mold, including the species ''Polysphondylium pallidum''. The genus was circumscribed by German mycologist Julius Oscar Brefeld in 1884. Species *''Polysphondylium acuminatum'' Vadell & Cavender 1998 nom. inv. *''Polysphondylium aureum'' Hodgson & Wheller 2001 nom. inv. *''Polysphondylium fuscans'' Perrigo & Romeralo 2012 *''Polysphondylium laterosorum'' (Cavender 1970) Baldauf, Sheikh & Thulin 2017 *''Polysphondylium patagonicum'' Vadell et al. 2011 *'' Polysphondylium violaceum'' Brefeld 1885 See also *''Dictyostelium ''Dictyostelium'' is a genus of single- and multi-celled eukaryotic, phagotrophic bacterivores. Though they are Protista and in no way fungal, they traditionally are known as "slime molds". They are present in most terrestrial ecosystems ...'' so-called cellular slime mold. References Amoebozoa genera Mycetozoa Taxa named by Julius Oscar Brefeld {{Amoebozoa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barettin
Barettin is a brominated alkaloid made of a dehydrogenated brominated derivative of tryptophan linked by two peptide bonds to an arginine residue, forming a 2,5-diketopiperazine nucleus. It is a cyclic dipeptide. Barettin is the major compound in the deep-sea sponge ''Geodia barretti ''Geodia barretti'' is a massive deep-sea sponge species found in the boreal waters of the North Atlantic Ocean, and is fairly common on the coasts of Norway and Sweden. It is a dominant species in boreal sponge grounds. Supported by morphology ...''. It was isolated for the first time in 1986 by Göran Lidgren, Lars Bohlin and Jan Bergman at Uppsala University, Sweden but the correct chemical structure was determined later in 2002. Barettin is written with one 'r' because the authors misspelled ''Geodia barretti'' with one 'r' in the original paper. Barettin seems to show antioxidant and anti-inflammatory properties which could be used in treating diseases that affect the immune system and dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
