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49-892: The primary ingredient in the Lipovitan product line is taurine . Stronger formulas of the drink include Lipovitan D , which contains 1000 mg of taurine, 20 mg of nicotinic acid extract (vitamin B 3 ), 5 mg each of vitamin B1, B2 and B6, and 50 mg of caffeine. Lipovitan D Super contains 2000 mg of taurine and 300 mg of arginine . MAXIO contains 3000 mg of taurine. The warning label on all of its products say not to consume more than 100 ml per day. Lipovitan products are sold in Japan and in stores in countries that carry Asian products. The introduction of Lipovitan predates Red Bull 's precursor Krating Daeng by 14 years, having been first released in 1962. Arginine

98-425: A 10% survival rate. In 2020 an article was published that suggests L-cysteine might also work in humans. N -Acetyl- l -cysteine is a derivative of cysteine wherein an acetyl group is attached to the nitrogen atom. This compound is sold as a dietary supplement, and used as an antidote in cases of acetaminophen overdose. Cysteine is required by sheep to produce wool. It is an essential amino acid that

147-469: A catalytic cysteine. These roles are typically limited to the intracellular milieu, where the environment is reducing, and cysteine is not oxidized to cystine. Cysteine is considered a "newcomer" amino acid, being the 17th amino acid incorporated into the genetic code . Similar to other later-added amino acids such as methionine , tyrosine , and tryptophan , cysteine exhibits strong nucleophilic and redox-active properties. These properties contribute to

196-503: A diet lacking in this essential amino acid are dilated cardiomyopathy , and reproductive failure in female cats . Decreased plasma taurine concentration has been demonstrated to be associated with feline dilated cardiomyopathy . Unlike CRD, the condition is reversible with supplementation. Taurine is now a requirement of the Association of American Feed Control Officials (AAFCO) and any dry or wet food product labeled approved by

245-494: A family of golden retrievers suffering from taurine deficiency treatable with supplementation. Foxes on fur farms also appear to require dietary taurine. The rhesus , cebus and cynomolgus monkeys each require taurine at least in infancy. The giant anteater also requires taurine. Taurine appears to be essential for the development of passerine birds. Many passerines seek out taurine-rich spiders to feed their young, particularly just after hatching. Researchers compared

294-492: A high affinity for heavy metals , so that proteins containing cysteine, such as metallothionein , will bind metals such as mercury, lead, and cadmium tightly. In the translation of messenger RNA molecules to produce polypeptides, cysteine is coded for by the UGU and UGC codons . Cysteine has traditionally been considered to be a hydrophilic amino acid, based largely on the chemical parallel between its sulfhydryl group and

343-422: A higher price. The typical synthetic route involves fermentation with an artificial E. coli strain. Alternatively, Evonik (formerly Degussa) introduced a route from substituted thiazolines . Pseudomonas thiazolinophilum hydrolyzes racemic 2‑amino-Δ ‑thiazoline-4‑carboxylic acid to l ‑cysteine. In animals, biosynthesis begins with the amino acid serine . The sulfur

392-646: A low p K a ensuring that it is fully ionized to the sulfonate at the pHs found in the intestinal tract. Synthetic taurine is obtained by the ammonolysis of isethionic acid (2-hydroxyethanesulfonic acid), which in turn is obtained from the reaction of ethylene oxide with aqueous sodium bisulfite . A direct approach involves the reaction of aziridine with sulfurous acid . In 1993, about 5000–6000  tonnes of taurine were produced for commercial purposes: 50% for pet food and 50% in pharmaceutical applications. As of 2010, China alone has more than 40 manufacturers of taurine. Most of these enterprises employ

441-510: A non essential amino acid , in rare cases, cysteine may be essential for infants, the elderly, and individuals with certain metabolic diseases or who suffer from malabsorption syndromes . Cysteine can usually be synthesized by the human body under normal physiological conditions if a sufficient quantity of methionine is available. The majority of l -cysteine is obtained industrially by hydrolysis of animal materials, such as poultry feathers or hog hair. Despite widespread rumor, human hair

490-407: A nucleophiles. Aside from its oxidation to cystine, cysteine participates in numerous post-translational modifications . The nucleophilic sulfhydryl group allows cysteine to conjugate to other groups, e.g., in prenylation . Ubiquitin ligases transfer ubiquitin to its pendant, proteins, and caspases , which engage in proteolysis in the apoptotic cycle. Inteins often function with the help of

539-481: A preventive or antidote for some of the negative effects of alcohol, including liver damage and hangover . It counteracts the poisonous effects of acetaldehyde . It binds to acetaldehyde to form the low-toxicity heterocycle methyl thioproline . In a rat study, test animals received an LD 90 dose of acetaldehyde. Those that received cysteine had an 80% survival rate; when both cysteine and thiamine were administered, all animals survived. The control group had

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588-449: A salt substitute. Prematurely born infants are believed to lack the enzymes needed to convert cystathionine to cysteine , and may, therefore, become deficient in taurine. Taurine is present in breast milk , and has been added to many infant formulas as a measure of prudence since the early 1980s. However, this practice has never been rigorously studied, and as such it has yet to be proven to be necessary, or even beneficial. Taurine

637-433: Is encoded by the codons UGU and UGC. Like other amino acids (not as a residue of a protein), cysteine exists as a zwitterion . Cysteine has l chirality in the older d / l notation based on homology to d - and l -glyceraldehyde. In the newer R / S system of designating chirality, based on the atomic numbers of atoms near the asymmetric carbon, cysteine (and selenocysteine) have R chirality, because of

686-542: Is "considered to be a skin and eye irritant and skin sensitiser, and to be hazardous if inhaled;" it may be safe to consume up to 6 grams of taurine per day. Other sources indicate that taurine is safe for supplemental intake in normal healthy adults at up to 3 grams per day. A 2008 review found no documented reports of negative or positive health effects associated with the amount of taurine used in energy drinks, concluding, "The amounts of guarana , taurine, and ginseng found in popular energy drinks are far below

735-424: Is an example of a protein with cystine crosslinking, wherein two separate peptide chains are connected by a pair of disulfide bonds. Protein disulfide isomerases catalyze the proper formation of disulfide bonds ; the cell transfers dehydroascorbic acid to the endoplasmic reticulum , which oxidizes the environment. In this environment, cysteines are, in general, oxidized to cystine and are no longer functional as

784-451: Is an ingredient in some energy drinks in amounts of 1–3 g per serving. A 1999 assessment of European consumption of energy drinks found that taurine intake was 40–400 mg per day. Taurine is not regarded as an essential human dietary nutrient and has not been assigned recommended intake levels. High-quality clinical studies to determine possible effects of taurine in the body or following dietary supplementation are absent from

833-420: Is conditional, differing by species and growth stage. The Olive flounder , for example, has lower capacity to synthesize taurine compared to the rainbow trout . Juvenile fish are less efficient at taurine biosyntheis due to reduced cysteine sulfinate decarboxylase levels. Cysteine Cysteine (symbol Cys or C ; / ˈ s ɪ s t ɪ iː n / ) is a semiessential proteinogenic amino acid with

882-437: Is converted to O -acetylserine by the enzyme serine transacetylase . The enzyme cysteine synthase , using sulfide sources, converts this ester into cysteine, releasing acetate. The cysteine sulfhydryl group is nucleophilic and easily oxidized. The reactivity is enhanced when the thiol is ionized, and cysteine residues in proteins have pK a values close to neutrality, so are often in their reactive thiolate form in

931-422: Is converted to cysteic acid by 3′-phosphoadenylyl sulfate :2-aminoacrylate C - sulfotransferase . Cysteic acid is converted to taurine by cysteine sulfinic acid decarboxylase . Taurine occurs naturally in fish and meat. The mean daily intake from omnivore diets was determined to be around 58 mg (range 9–372 mg ), and to be low or negligible from a vegan diet. Typical taurine consumption in

980-424: Is derived from methionine , which is converted to homocysteine through the intermediate S -adenosylmethionine . Cystathionine beta-synthase then combines homocysteine and serine to form the asymmetrical thioether cystathionine . The enzyme cystathionine gamma-lyase converts the cystathionine into cysteine and alpha-ketobutyrate . In plants and bacteria , cysteine biosynthesis also starts from serine, which

1029-416: Is extracted from cysteine, which is converted to alanine in the process. Beyond the iron-sulfur proteins, many other metal cofactors in enzymes are bound to the thiolate substituent of cysteinyl residues. Examples include zinc in zinc fingers and alcohol dehydrogenase , copper in the blue copper proteins , iron in cytochrome P450 , and nickel in the [NiFe]- hydrogenases . The sulfhydryl group also has

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1078-451: Is negligible; so it must be biosynthesized from its constituent amino acids, cysteine, glycine , and glutamic acid . While glutamic acid is usually sufficient because amino acid nitrogen is recycled through glutamate as an intermediary, dietary cysteine and glycine supplementation can improve synthesis of glutathione. Cysteine is an important source of sulfide in human metabolism . The sulfide in iron-sulfur clusters and in nitrogenase

1127-475: Is no good clinical evidence that taurine supplements provide any benefit to human health. Taurine is used as a food additive for cats (who require it as an essential nutrient), dogs, and poultry. Taurine concentrations in land plants are low or undetectable, but up to 1000 nmol/g wet weight have been found in algae . Taurine exists as a zwitterion H 3 N CH 2 CH 2 SO − 3 , as verified by X-ray crystallography . The sulfonic acid has

1176-474: Is rarely a source material. Indeed, food additive or cosmetic product manufactures may not legally source from human hair in the European Union. Some animal-originating sources of l -cysteine as a food additive contravene kosher, halal, vegan, or vegetarian diets. To avoid this problem, synthetic l -cysteine, compliant with Jewish kosher and Muslim halal laws, is also available, albeit at

1225-411: Is relatively upregulated in mitochondrially encoded proteins. Cysteine, mainly the l - enantiomer , is a precursor in the food, pharmaceutical, and personal-care industries. One of the largest applications is the production of flavors. For example, the reaction of cysteine with sugars in a Maillard reaction yields meat flavors. l -Cysteine is also used as a processing aid for baking. In

1274-399: Is taken in from their feed. As a consequence, during drought conditions, sheep produce less wool; however, transgenic sheep that can make their own cysteine have been developed. Being multifunctional, cysteine undergoes a variety of reactions. Much attention has focused on protecting the sulfhydryl group. Methylation of cysteine gives S-methylcysteine . Treatment with formaldehyde gives

1323-401: Is the main active ingredient in the modified Red Bull sold in Japan. The Japan national rugby team is sponsored by Lipovitan D. This non-alcoholic drink –related article is a stub . You can help Misplaced Pages by expanding it . Taurine Taurine ( / ˈ t ɔː r iː n / ), or 2-aminoethanesulfonic acid , is a non-proteinogenic naturally occurring amino sulfonic acid that

1372-408: Is widely distributed in animal tissues. It is a major constituent of bile and can be found in the large intestine , and accounts for up to 0.1% of total human body weight. Taurine is named after Latin taurus ( cognate to Ancient Greek ταῦρος, taûros ) meaning bull or ox , as it was first isolated from ox bile in 1827 by German scientists Friedrich Tiedemann and Leopold Gmelin . It

1421-417: The ethanolamine method to produce a total annual production of about 3000  tonnes. In the laboratory, taurine can be produced by alkylation of ammonia with bromoethanesulfonate salts. Taurine is naturally derived from cysteine . Mammalian taurine synthesis occurs in the liver via the cysteine sulfinic acid pathway. In this pathway, cysteine is first oxidized to its sulfinic acid, catalyzed by

1470-421: The formula HOOC−CH(−NH 2 )−CH 2 −SH . The thiol side chain in cysteine often participates in enzymatic reactions as a nucleophile . Cysteine is chiral, but both D and L -cysteine are found in nature. L ‑Cysteine is a protein monomer in all biota, and D -cysteine acts as a signaling molecule in mammalian nervous systems. Cysteine is named after its discovery in urine, which comes from

1519-476: The hydroxyl groups in the side chains of other polar amino acids. However, the cysteine side chain has been shown to stabilize hydrophobic interactions in micelles to a greater degree than the side chain in the nonpolar amino acid glycine and the polar amino acid serine. In a statistical analysis of the frequency with which amino acids appear in various proteins, cysteine residues were found to associate with hydrophobic regions of proteins. Their hydrophobic tendency

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1568-465: The AAFCO should have a minimum of 0.1% taurine in dry food and 0.2% in wet food. Studies suggest the amino acid should be supplied at 10 mg per kilogram of bodyweight per day for domestic cats. A number of other mammals also have a requirement for taurine. While the majority of dogs can synthesize taurine, case reports have described a singular American cocker spaniel , 19 Newfoundland dogs , and

1617-464: The American diet is about 123–178 mg per day. Taurine is partially destroyed by heat in processes such as baking and boiling. This is a concern for cat food, as cats have a dietary requirement for taurine and can easily become deficient. Either raw feeding or supplementing taurine can satisfy this requirement. Both lysine and taurine can mask the metallic flavor of potassium chloride ,

1666-423: The amounts expected to deliver either therapeutic benefits or adverse events". Cats lack the enzymatic machinery ( sulfinoalanine decarboxylase ) to produce taurine and must therefore acquire it from their diet. A taurine deficiency in cats can lead to retinal degeneration and eventually blindness – a condition known as central retinal degeneration as well as hair loss and tooth decay. Other effects of

1715-606: The behaviours and development of birds fed a taurine-supplemented diet to a control diet and found the juveniles fed taurine-rich diets as neonates were much larger risk takers and more adept at spatial learning tasks. Under natural conditions, each blue tit nestling receive 1 mg of taurine per day from parents. Taurine can be synthesized by chickens. Supplementation has no effect on chickens raised under adequate lab conditions, but seems to help with growth under stresses such as heat and dense housing. Species of fish, mostly carnivorous ones, show reduced growth and survival when

1764-412: The cell. Because of its high reactivity, the sulfhydryl group of cysteine has numerous biological functions. Due to the ability of thiols to undergo redox reactions, cysteine and cysteinyl residues have antioxidant properties. Its antioxidant properties are typically expressed in the tripeptide glutathione , which occurs in humans and other organisms. The systemic availability of oral glutathione (GSH)

1813-431: The corresponding sulfinic acid and sulfonic acid . Cysteine residues play a valuable role by crosslinking proteins, which increases the rigidity of proteins and also functions to confer proteolytic resistance (since protein export is a costly process, minimizing its necessity is advantageous). Inside the cell, disulfide bridges between cysteine residues within a polypeptide support the protein's tertiary structure. Insulin

1862-621: The depletion of cysteine from respiratory chain complexes, such as Complexes I and IV , since reactive oxygen species ( ROS ) produced by the respiratory chain can react with the cysteine residues in these complexes, leading to dysfunctional proteins and potentially contributing to aging. The primary response of a protein to ROS is the oxidation of cysteine and the loss of free thiol groups, resulting in increased thiyl radicals and associated protein cross-linking. In contrast, another sulfur-containing, redox-active amino acid, methionine, does not exhibit these biochemical properties and its content

1911-402: The enzyme cysteine dioxygenase . Cysteine sulfinic acid, in turn, is decarboxylated by sulfinoalanine decarboxylase to form hypotaurine . Hypotaurine is enzymatically oxidized to yield taurine by hypotaurine dehydrogenase . Taurine is also produced by the transsulfuration pathway , which converts homocysteine into cystathionine . The cystathionine is then converted to hypotaurine by

1960-407: The extracellular medium. Since most cellular compartments are reducing environments , disulfide bonds are generally unstable in the cytosol with some exceptions as noted below. Disulfide bonds in proteins are formed by oxidation of the sulfhydryl group of cysteine residues. The other sulfur-containing amino acid, methionine, cannot form disulfide bonds. More aggressive oxidants convert cysteine to

2009-594: The field of personal care, cysteine is used for permanent-wave applications, predominantly in Asia. Again, the cysteine is used for breaking up the disulfide bonds in the hair 's keratin . Cysteine is a very popular target for site-directed labeling experiments to investigate biomolecular structure and dynamics. Maleimides selectively attach to cysteine using a covalent Michael addition . Site-directed spin labeling for EPR or paramagnetic relaxation-enhanced NMR also uses cysteine extensively. Cysteine has been proposed as

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2058-405: The fish-based feed in their food is replaced with soy meal or feather meal. Taurine has been identified as the factor responsible for this phenomenon; supplementation of taurine to plant-based fish feed reverses these effects. Future aquaculture is expected to use more of these more environmentally-friendly protein sources, so supplementation would become more important. The need of taurine in fish

2107-490: The literature. Preliminary human studies on the possible effects of taurine supplementation have been inadequate due to low subject numbers, inconsistent designs, and variable doses. Preliminary studies have suggested that supplementing with taurine may increase exercise capacity and affects lipid profiles in individuals with diabetes. According to the European Food Safety Authority , taurine

2156-503: The presence of sulfur (or selenium) as a second neighbor to the asymmetric carbon atom. The remaining chiral amino acids, having lighter atoms in that position, have S chirality. Replacing sulfur with selenium gives selenocysteine . Cysteinyl is a residue in high- protein foods. Some foods considered rich in cysteine include poultry, eggs, beef, and whole grains. In high-protein diets, cysteine may be partially responsible for reduced blood pressure and stroke risk. Although classified as

2205-406: The sequential action of three enzymes: cystathionine gamma-lyase , cysteine dioxygenase , and cysteine sulfinic acid decarboxylase. Hypotaurine is then oxidized to taurine as described above. A pathway for taurine biosynthesis from serine and sulfate is reported in microalgae , developing chicken embryos , and chick liver . Serine dehydratase converts serine to 2-aminoacrylate , which

2254-416: The tendency of cysteines to form disulfide bonds in proteins. Therefore, cysteine is now often grouped among the hydrophobic amino acids, though it is sometimes also classified as slightly polar, or polar. Most cysteine residues are covalently bonded to other cysteine residues to form disulfide bonds , which play an important role in the folding and stability of some proteins, usually proteins secreted to

2303-426: The urinary bladder or cyst, from Greek κύστη kýsti , "bladder". The thiol is susceptible to oxidation to give the disulfide derivative cystine , which serves an important structural role in many proteins . In this case, the symbol Cyx is sometimes used. The deprotonated form can generally be described by the symbol Cym as well. When used as a food additive, cysteine has the E number E920. Cysteine

2352-405: Was discovered in human bile in 1846 by Edmund Ronalds . Although taurine is abundant in human organs with diverse putative roles, it is not an essential human dietary nutrient and is not included among nutrients with a recommended intake level . Taurine is synthesized naturally in the human liver from methionine and cysteine . Taurine is commonly sold as a dietary supplement , but there

2401-470: Was equivalent to that of known nonpolar amino acids such as methionine and tyrosine (tyrosine is polar aromatic but also hydrophobic ), those of which were much greater than that of known polar amino acids such as serine and threonine . Hydrophobicity scales , which rank amino acids from most hydrophobic to most hydrophilic, consistently place cysteine towards the hydrophobic end of the spectrum, even when they are based on methods that are not influenced by

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