Classification Term: 2163
L-alpha-amino acids (ontology term: CHEMONTID:0004146)
Alpha amino acids which have the L-configuration of the alpha-carbon atom." []
found 97 associated metabolites at no_class-level_8
metabolite taxonomy ontology rank level.
Ancestor: Alpha amino acids
Child Taxonomies: S-alkyl-L-cysteines
L-Threonine
L-threonine is an optically active form of threonine having L-configuration. It has a role as a nutraceutical, a micronutrient, a Saccharomyces cerevisiae metabolite, a plant metabolite, an Escherichia coli metabolite, a human metabolite, an algal metabolite and a mouse metabolite. It is an aspartate family amino acid, a proteinogenic amino acid, a threonine and a L-alpha-amino acid. It is a conjugate base of a L-threoninium. It is a conjugate acid of a L-threoninate. It is an enantiomer of a D-threonine. It is a tautomer of a L-threonine zwitterion. An essential amino acid occurring naturally in the L-form, which is the active form. It is found in eggs, milk, gelatin, and other proteins. L-Threonine is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Threonine is an essential amino acid in humans (provided by food), Threonine is an important residue of many proteins, such as tooth enamel, collagen, and elastin. An important amino acid for the nervous system, threonine also plays an important role in porphyrin and fat metabolism and prevents fat buildup in the liver. Useful with intestinal disorders and indigestion, threonine has also been used to alleviate anxiety and mild depression. (NCI04) Threonine is an essential amino acid in humans. It is abundant in human plasma, particularly in newborns. Severe deficiency of threonine causes neurological dysfunction and lameness in experimental animals. Threonine is an immunostimulant which promotes the growth of thymus gland. It also can probably promote cell immune defense function. This amino acid has been useful in the treatment of genetic spasticity disorders and multiple sclerosis at a dose of 1 gram daily. It is highly concentrated in meat products, cottage cheese and wheat germ. The threonine content of most of the infant formulas currently on the market is approximately 20\\\\\\% higher than the threonine concentration in human milk. Due to this high threonine content the plasma threonine concentrations are up to twice as high in premature infants fed these formulas than in infants fed human milk. The whey proteins which are used for infant formulas are sweet whey proteins. Sweet whey results from cheese production. Threonine catabolism in mammals appears to be due primarily (70-80\\\\\\%) to the activity of threonine dehydrogenase (EC 1.1.1.103) that oxidizes threonine to 2-amino-3-oxobutyrate, which forms glycine and acetyl CoA, whereas threonine dehydratase (EC 4.2.1.16) that catabolizes threonine into 2-oxobutyrate and ammonia, is significantly less active. Increasing the threonine plasma concentrations leads to accumulation of threonine and glycine in the brain. Such accumulation affects the neurotransmitter balance which may have consequences for the brain development during early postnatal life. Thus, excessive threonine intake during infant feeding should be avoided. (A3450). An essential amino acid occurring naturally in the L-form, which is the active form. It is found in eggs, milk, gelatin, and other proteins. See also: Amlisimod (monomer of) ... View More ... Threonine (Thr) or L-threonine is an alpha-amino acid. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. L-threonine is one of 20 proteinogenic amino acids, i.e., the amino acids used in the biosynthesis of proteins. Threonine is found in all organisms ranging from bacteria to plants to animals. It is classified as a polar, uncharged (at physiological pH), aliphatic amino acid. Threonine is sometimes considered as a branched chain amino acid. Threonine was actually the last of the 20 amino acids to be discovered (in 1938). It was named threonine because it was similar in structure to threonic acid, a four-carbon monosaccharide. Threonine is an essential amino acid in humans, meaning the body cannot synthesize it and that it must be obtained from the diet. Foods high in threonine include cottage cheese, poultry, fish, meat, lentils, black turtle bean and sesame seeds. Adult humans require about 20 mg/kg body weight/day. In plants and microorganisms, threonine is synthesized from aspartic acid via alpha-aspartyl-semialdehyde and homoserine. In proteins, the threonine residue is susceptible to numerous posttranslational modifications. The hydroxyl side-chain can undergo O-linked glycosylation and phosphorylation through the action of a threonine kinase. Threonine is abundant in human plasma, particularly in newborns. Severe deficiency of threonine causes neurological dysfunction and lameness in experimental animals. Threonine is an immunostimulant which promotes the growth of thymus gland. It also can probably promote cell immune defense function. The threonine content of most of the infant formulas currently on the market is approximately 20\\\\\\% higher than the threonine concentration in human milk. Due to this high threonine content the plasma threonine concentrations are up to twice as high in premature infants fed these formulas than in infants fed human milk. The whey proteins which are used for infant formulas are sweet whey proteins. Sweet whey results from cheese production. Increasing the threonine plasma concentrations leads to accumulation of threonine and glycine in the brain. Such accumulation affects the neurotransmitter balance which may have consequences for the brain development during early postnatal life. Thus, excessive threonine intake during infant feeding should be avoided. (PMID 9853925). Threonine is metabolized in at least two ways. In many animals it is converted to pyruvate via threonine dehydrogenase. An intermediate in this pathway can undergo thiolysis with CoA to produce acetyl-CoA and glycine. In humans the gene for threonine dehydrogenase is an inactive pseudogene, so threonine is converted to alpha-ketobutyrate. From wide variety of protein hydrolysates. Dietary supplement, nutrient L-Threonine. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=72-19-5 (retrieved 2024-07-01) (CAS RN: 72-19-5). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). DL-Threonine, an essential amino acid, has the potential to treat hypostatic leg ulceration[1]. L-Threonine is a natural amino acid, can be produced by microbial fermentation, and is used in food, medicine, or feed[1]. L-Threonine is a natural amino acid, can be produced by microbial fermentation, and is used in food, medicine, or feed[1].
L-Tryptophan betaine
Hypaphorine is an amino acid betaine obtaine by exhaustive methylation of the alpha-amino group of L-tryptophan with concomitant deprotonation of the carboxy group. It has a role as a plant metabolite, a xenobiotic and a fungal metabolite. It is an amino-acid betaine, a L-tryptophan derivative and an indole alkaloid. Hypaphorine is a natural product found in Erythrina suberosa, Erythrina subumbrans, and other organisms with data available. Lenticin or hypaphorine is a compound found in lentil extracts. It can also be detected in blood after an individual has consumed lentils and may therefore serve as a food biomarker. Lenticin is an indole alkaloid that is essentially an N-methylated form of tryptophan. It is known to be a sleep-inducing compound (PMID: 18571406). In plants it is an agonist of the plant hormone indole acetic acid. An amino acid betaine obtaine by exhaustive methylation of the alpha-amino group of L-tryptophan with concomitant deprotonation of the carboxy group. (+)-Hypaphorine. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=487-58-1 (retrieved 2024-07-01) (CAS RN: 487-58-1). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Hypaphorine is an indole alkaloid isolated from Caragana korshinskii, and with neurological and glucose-lowering effects in rodents[1]. Hypaphorine is an indole alkaloid isolated from Caragana korshinskii, and with neurological and glucose-lowering effects in rodents[1].
S-(1-Propenyl)-cysteine sulfoxide
S-(1-propenyl)-cysteine sulfoxide, also known as prensco, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. S-(1-propenyl)-cysteine sulfoxide is soluble (in water) and a moderately acidic compound (based on its pKa). S-(1-propenyl)-cysteine sulfoxide can be found in a number of food items such as babassu palm, spirulina, elderberry, and cassava, which makes S-(1-propenyl)-cysteine sulfoxide a potential biomarker for the consumption of these food products. D000970 - Antineoplastic Agents D007004 - Hypoglycemic Agents
Se-Methylselenocysteine
Se-Methylselenocysteine (SeMSC) is a naturally occurring seleno-amino acid that is synthesized by plants such as garlic, astragalus, onions, and broccoli. It cannot be synthesized by higher animals. Unlike selenomethionine, which is incorporated into proteins in place of methionine, SeMSC is not incorporated into any proteins, thereby being fully available for the synthesis of selenium-containing enzymes such as glutathione peroxidase. Selenomethionine is the major seleno-compound in cereal grains (wheat grain, maize, and rice), soybeans, and enriched yeast. Seleno-compounds present in plants may have a profound effect upon the health of animals and human subjects. It is now known that the total Se content cannot be used as an indication of its efficacy, but knowledge of individual selenocompounds is necessary to fully assess the significance. Thus, speciation of the seleno-compounds has moved to the forefront. Since animals and man are dependent upon plants for their nutritional requirements, this makes the types of seleno-compounds in plants even more critical. Se enters the food chain through incorporation into plant proteins, mostly as selenocysteine and selenomethionine at normal Se levels. There are two possible pathways for the catabolism of selenomethionine: (1) a transsulfuration pathway via selenocystathionine to produce selenocysteine, which in turn is degraded to H2Se by the enzyme beta-lyase and (2) a transamination-decarboxylation pathway. It was estimated that 90\\\\% of methionine is metabolized through this pathway and thus could be also the major route for selenomethionine catabolism (PMID: 14748935 , Br J Nutr. 2004 Jan;91(1):11-28.). Selenomethionine is an amino acid containing selenium. The L-isomer of selenomethionine, known as Se-met and Sem, is a common natural food source of selenium. In vivo, selenomethionine is randomly incorporated instead of methionine and is readily oxidized. Its antioxidant activity arises from its ability to deplete reactive species. Selenium and sulfur are chalcogen elements that share many chemical properties and the substitution of methionine to selenomethionine may have no effect on protein structure and function. However, the incorporation of selenomethionine into tissue proteins and keratin in horses causes alkali disease. Alkali disease is characterized by emaciation, loss of hair, deformation and shedding of hooves, loss of vitality, and erosion of the joints of long bones. Se-methyl-L-selenocysteine is an L-alpha-amino acid compound having methylselanylmethyl as the side-chain. It has a role as an antineoplastic agent. It is a Se-methylselenocysteine, a non-proteinogenic L-alpha-amino acid and a L-selenocysteine derivative. It is a conjugate base of a Se-methyl-L-selenocysteinium. It is a conjugate acid of a Se-methyl-L-selenocysteinate. It is an enantiomer of a Se-methyl-D-selenocysteine. It is a tautomer of a Se-methyl-L-selenocysteine zwitterion. Methylselenocysteine has been used in trials studying the prevention of Prostate Carcinoma and No Evidence of Disease. Se-Methylselenocysteine is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Methylselenocysteine is a naturally occurring organoselenium compound found in many plants, including garlic, onions, and broccoli, with potential antioxidant and chemopreventive activities. Se-Methyl-seleno-L-cysteine (MSC) is an amino acid analogue of cysteine in which a methylselenium moiety replaces the sulphur atom of cysteine. This agent acts as an antioxidant when incorporated into glutathione peroxidase and has been shown to exhibit potent chemopreventive activity in animal models. Se-Methylselenocysteine (SeMSC) is a naturally occurring seleno-amino acid that is synthesized by plants such as garlic, astragalus, onions and broccoli. Unlike selenomethionine, which is incorporated into proteins in place of methionine, SeMSC is not incorporated into any proteins, thereby being fully available for the synthesis of selenium-containing enzymes such as glutathione peroxidase. 3-(Methylseleno)alanine is found in many foods, some of which are common cabbage, white cabbage, lima bean, and cauliflower. D020011 - Protective Agents > D016588 - Anticarcinogenic Agents C26170 - Protective Agent > C275 - Antioxidant D000970 - Antineoplastic Agents Se-Methylselenocysteine, a precursor of Methylselenol, has potent cancer chemopreventive activity and anti-oxidant activity. Se-Methylselenocysteine is orally bioavailable, and induces apoptosis[1][2]. Se-Methylselenocysteine, a precursor of Methylselenol, has potent cancer chemopreventive activity and anti-oxidant activity. Se-Methylselenocysteine is orally bioavailable, and induces apoptosis[1][2].
L-Canaline
L-canaline, also known as L-2-amino-4-(aminooxy)butyric acid, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. L-canaline is soluble (in water) and a moderately acidic compound (based on its pKa). L-canaline can be found in a number of food items such as mulberry, rape, grape, and black chokeberry, which makes L-canaline a potential biomarker for the consumption of these food products. L-canaline is a substrate for ornithine aminotransferase resulting in the synthesis of L-ureidohomoserine (the corresponding analog of L-citrulline). In turn, the latter forms L-canavaninosuccinic acid in a reaction mediated by argininosuccinic acid synthetase. L-Canavaninosuccinic acid is cleaved to form L-canavanine by argininosuccinic acid synthetase. By these sequential reactions, the canaline-urea cycle (analogous to the ornithine-urea cycle) is formed. Every time a canavanine molecule runs through the canaline-urea cycle, the two terminal nitrogen atoms are released as urea. Urea is an important by-product of this reaction sequence because it makes ammonicial ammonia (urease-mediated) that is available to support intermediary nitrogen metabolism. L-canaline can by reductively cleaved to L-homoserine, a non-protein amino acid of great importance in the formation of a host of essential amino acids. In this way, the third nitrogen atom of canavanine enters into the reactions of nitrogen metabolism of the plant. As homoserine, its carbon skeleton also finds an important use . L-canaline is a non-proteinogenic L-alpha-amino acid that is L-homoserine in which the hydroxy group at position 4 is substituted by an aminooxy group. It has been isolated from legumes and plays an essential role in lugume chemical defense against insects. It has a role as a plant metabolite, an antineoplastic agent, an antimetabolite and a phytogenic insecticide. It is functionally related to a L-homoserine. It is a tautomer of a L-canaline zwitterion. Canavanine reacts with water to produce L-canaline and urea. The reaction is catalyzed by arginase. L-canaline reacts with carbamoyl-phosphate to produce O-ureidohomoserine and phosphate. The reaction is catalyzed by ornithine carbamoyltransferase. A non-proteinogenic L-alpha-amino acid that is L-homoserine in which the hydroxy group at position 4 is substituted by an aminooxy group. It has been isolated from legumes and plays an essential role in lugume chemical defense against insects.
Selenomethionine
L-selenomethionine is the L-enantiomer of selenomethionine. It is an enantiomer of a D-selenomethionine. It is a tautomer of a L-selenomethionine zwitterion. Selenomethionine is a naturally occuring amino acid in some plant materials such as cereal grains, soybeans and enriched yeast but it cannot be synthesized from animals or humans. It can be produced from post-structural modifications. *In vivo*, selenomethionine plays an essential role in acting as an antioxidant, where it depletes reactive oxygen species (ROS) and aids in the formation and recycling of glutathione, another important antioxidant. In comparison to selenite, which is the inorganic form of selenium, the organic form of selenomethionine is more readily absorbed in the human body. Selenomethionin is used in biochemical laboratories where its incorporation into proteins that need to be visualized enhances the performance of X-ray crystallography. L-Selenomethionine is the amino acid methionine with selenium substituting for the sulphur moiety. Methionine is an essential amino acid in humans, whereas selenium is a free-radical scavenging anti-oxidant, essential for the protection of various tissues from the damages of lipid peroxidation. As a trace mineral that is toxic in high doses, selenium is a cofactor for glutathione peroxidase, an anti-oxidant enzyme that neutralizes hydrogen peroxide. L-Selenomethionine is considered a safe, efficacious form of selenium and is readily bioavailable. Selenium may be chemoprotective for certain cancers, particularly prostate cancer. (NCI04) Diagnostic aid in pancreas function determination. Selenomethionine (CAS: 1464-42-2) is an amino acid containing selenium that cannot be synthesized by higher animals but can be obtained from plant material. Selenomethionine is the major seleno-compound in cereal grains (wheat grain, maize, and rice), soybeans, and enriched yeast. Seleno-compounds present in plants may have a profound effect on the health of animals and human subjects. It is now known that the total Se content cannot be used as an indication of its efficacy, but knowledge of individual selenocompounds is necessary to fully assess the significance. Thus, speciation of the seleno-compounds has moved to the forefront. Since animals and man are dependent upon plants for their nutritional requirements, this makes the types of seleno-compounds in plants even more critical. Se enters the food chain through incorporation into plant proteins, mostly as selenocysteine and selenomethionine at normal Se levels. There are two possible pathways for the catabolism of selenomethionine. One is the transsulfuration pathway via selenocystathionine to produce selenocysteine, which in turn is degraded into H2Se by the enzyme beta-lyase. The other pathway is the transamination-decarboxylation pathway. It was estimated that 90\\\\% of methionine is metabolized through this pathway and thus could be also the major route for selenomethionine catabolism (PMID:14748935). Found in onion, cabbage, coco de mono (Lecythis elliptica), Brazil nuts (Bertholletia excelsa), wheat grains and other plants. Dietary supplement for avoidance of Se deficiency in humans and ruminants C26170 - Protective Agent > C275 - Antioxidant The L-enantiomer of selenomethionine. L-SelenoMethionine, an L-isomer of Selenomethionine, is a major natural food-form of selenium. L-SelenoMethionin is a cancer chemopreventive agent that can reduce cancer incidence by dietary supplementation and induce apoptosis of cancer cells. L-SelenoMethionine also can increase expression of glutathione peroxidase[1][2][3]. Selenomethionine is a naturally occurring amino acid containing selenium and is a common natural food source.
Mimosine
Mimosine is only found in individuals that have used or taken this drug. It is an antineoplastic alanine-substituted pyridine derivative isolated from Leucena glauca. [PubChem]Mimosine causes inhibition of DNA replication, changes in the progression of the cells in the cell cycle, and apoptosis. Mimosine appears to introduce breaks into DNA. Mimosine is an iron/zinc chelator. Iron depletion induces DNA double-strand breaks in treated cells, and activates a DNA damage response that results in focal phosphorylation of histones. This leads to inhibition of DNA replication and/or DNA elongation. Some studies indicate that mimosine prevents the initiation of DNA replication, whereas other studies indicate that mimosine disrupts elongation of the replication fork by impairing deoxyribonucleotide synthesis by inhibiting the activity of the iron-dependent enzyme ribonucleotide reductase and the transcription of the cytoplasmic serine hydroxymethyltransferase gene (SHMT). Inhibition of serine hydroxymethyltransferase is moderated by a zinc responsive unit located in front of the SHMT gene. L-mimosine is an L-alpha-amino acid that is propionic acid substituted by an amino group at position 2 and a 3-hydroxy-4-oxopyridin-1(4H)-yl group at position 3 (the 2S-stereoisomer). It a non-protein plant amino acid isolated from Mimosa pudica. It has a role as an EC 1.14.18.1 (tyrosinase) inhibitor and a plant metabolite. It is a non-proteinogenic L-alpha-amino acid and a member of 4-pyridones. It is functionally related to a propionic acid. It is a conjugate acid of a L-mimosine(1-). It is a tautomer of a L-mimosine zwitterion. Mimosine is an antineoplastic alanine-substituted pyridine derivative isolated from Leucena glauca. 3-Hydroxy-4-oxo-1(4H)-pyridinealanine. An antineoplastic alanine-substituted pyridine derivative isolated from Leucena glauca. An L-alpha-amino acid that is propionic acid substituted by an amino group at position 2 and a 3-hydroxy-4-oxopyridin-1(4H)-yl group at position 3 (the 2S-stereoisomer). It a non-protein plant amino acid isolated from Mimosa pudica. Mimosine, a tyrosine analog , can act as an antioxidant by its potent iron-binding activity[1]. Mimosine is a known chelator of Fe(III)[2]. Mimosine induces apoptosis through metal ion chelation, mitochondrial activation and ROS production in human leukemic cells[3]. Anti-cancer, antiinflammation. Mimosine, a tyrosine analog , can act as an antioxidant by its potent iron-binding activity[1]. Mimosine is a known chelator of Fe(III)[2]. Mimosine induces apoptosis through metal ion chelation, mitochondrial activation and ROS production in human leukemic cells[3]. Anti-cancer, antiinflammation.
2,3-Diaminopropionic acid
2,3-Diaminopropionic acid, also known as L-2,3-diaminopropanoate or Dpr, belongs to the class of organic compounds known as l-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom. 2,3-Diaminopropionic acid is a very hydrophobic molecule, practically insoluble in water, and relatively neutral. 2,3-Diaminopropionic acid (2,3-diaminopropionate) is a non-proteinogenic amino acid found in certain secondary metabolites, including zwittermicin A and tuberactinomycin.2,3-Diaminopropionate is formed by the pyridoxal phosphate (PLP) mediated amination of serine. 2,3-Diaminopropionic acid exists in all living organisms, ranging from bacteria to humans. 2,3-Diaminopropionic acid is a metabolite of b-oxalyl-L-a,b-diaminopropionic acid a neurotoxic amino acid (ODAP). (PMID 5774501) COVID info from PDB, Protein Data Bank Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS
5-Hydroxylysine
5-Hydroxylysine (Hyl), also known as hydroxylysine or 5-Hydroxy-L-lysine, belongs to the class of organic compounds known as L-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom. Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. 5-Hydroxylysine is a hydroxylated derivative of the amino acid lysine that is present in certain collagens, the chief structural protein of mammalian skin and connective tissue. 5-Hydroxylysine arises from a post-translational hydroxy modification of lysine and is biosynthesized from lysine via oxidation by lysyl hydroxylase enzymes. 5-Hydroxylysine can then undergo further modification by glycosylation, giving rise to galactosyl hydroxylysine (GH) and glucosylgalactosyl hydroxylysine (GGH). These glycosylated forms of hydroxylysine contribute to collagen’s unusual toughness and resiliency. The monoglycosylated, galactosyl-hydroxylysine is enriched in bone compared with the disaccharide form, glucosyl-galactosyl-hydroxylysine, which is the major form in skin. 5-Hydroxylysine exists in all eukaryotes, ranging from yeast to humans. It was first discovered in 1921 by Donald Van Slyke. Free forms of hydroxylysine arise through proteolytic degradation of collagen. Urinary excretion of 5-Hydroxylysine and its glycosides can be used as an index of collagen degradation, with high levels being indicative of more rapid or extensive collagen degradation (often seen in patients with thermal burns, Pagets disease of bone or hyperphosphatasia) (PMID: 404321). One of the natural protein-bound amino acids. Occurs free in plant tissues, e.g. Medicago sativa (alfalfa)
Aminoadipic acid
Aminoadipic acid (CAS: 542-32-5), also known as 2-aminoadipate, is a metabolite in the principal biochemical pathway of lysine. It is an intermediate in the metabolism (i.e. breakdown or degradation) of lysine and saccharopine. It antagonizes neuroexcitatory activity modulated by the glutamate receptor N-methyl-D-aspartate (NMDA). Aminoadipic acid has also been shown to inhibit the production of kynurenic acid, a broad spectrum excitatory amino acid receptor antagonist, in brain tissue slices (PMID: 8566117). Recent studies have shown that aminoadipic acid is elevated in prostate biopsy tissues from prostate cancer patients (PMID: 23737455). Mutations in DHTKD1 (dehydrogenase E1 and transketolase domain-containing protein 1) have been shown to cause human 2-aminoadipic aciduria and 2-oxoadipic aciduria via impaired decarboxylation of 2-oxoadipate to glutaryl-CoA, which is the last step in the lysine degradation pathway (PMID: 23141293). Aging, diabetes, sepsis, and renal failure are known to catalyze the oxidation of lysyl residues to form 2-aminoadipic acid in human skin collagen and potentially other tissues (PMID: 18448817). Proteolytic breakdown of these tissues can lead to the release of free 2-aminoadipic acid. Studies in rats indicate that aminoadipic acid (along with the three branched-chain amino acids: leucine, valine, and isoleucine) levels are elevated in the pre-diabetic phase and so aminoadipic acid may serve as a predictive biomarker for the development of diabetes (PMID: 15389298). Long-term hyperglycemia of endothelial cells can also lead to elevated levels of aminoadipate which is thought to be a sign of lysine breakdown through oxidative stress and reactive oxygen species (ROS) (PMID: 21961526). 2-Aminoadipate is a potential small-molecule marker of oxidative stress (PMID: 21647514). Therefore, depending on the circumstances aminoadipic acid can act as an acidogen, a diabetogen, an atherogen, and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A diabetogen is a compound that can lead to type 2 diabetes. An atherogen is a compound that leads to atherosclerosis and cardiovascular disease. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of aminoadipic acid are associated with at least two inborn errors of metabolism including 2-aminoadipic aciduria and 2-oxoadipic aciduria. Aminoadipic acid is an organic acid and abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart abnormalities, kidney abnormalities, liver damage, seizures, coma, and possibly death. These are also the characteristic symptoms of the untreated IEMs mentioned above. Many affected children with organic acidemias experience intellectual disability or delayed development. In adults, acidosis or acidemia is characterized by headaches, confusion, feeling tired, tremors, sleepiness, and seizures. As a diabetogen, serum aminoadipic levels appear to regulate glucose homeostasis and have been highly predictive of individuals who later develop diabetes (PMID: 24091325). In particular, aminoadipic acid lowers fasting plasma glucose levels and enhances insulin secretion from human islets. As an atherogen, aminoadipic acid has been found to be produced at high levels via protein lysine oxidation in atherosclerotic plaques (PMID: 28069522). A metabolite in the principal biochemical pathway of lysine. It antagonizes neuroexcitatory activity modulated by the glutamate receptor, N-methyl-D-aspartate; (NMDA). L-α-Aminoadipic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=1118-90-7 (retrieved 2024-07-01) (CAS RN: 1118-90-7). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Aminoadipic acid is an intermediate in the metabolism of lysine and saccharopine. Aminoadipic acid is an intermediate in the metabolism of lysine and saccharopine.
Biocytin
Biocytin is a naturally occurring low molecular weight analog of biotin, and a primary source of this essential metabolite for mammals. Biotinidase acts as a hydrolase by cleaving biocytin and biotinyl-peptides, thereby liberating biotin for reutilization. Mammals cannot synthesize biotin and, therefore, derive the vitamin from dietary sources or from the endogenous turnover of the carboxylases. Free biotin can readily enter the biotin pool, whereas holocarboxylases or other biotin-containing proteins must first be degraded proteolytically to biocytin (biotinyl-e-lysine) or biotinyl-peptides. Biocytin is also an especially versatile marker for neuroanatomical investigations, shown that may have multiple applications, especially for labeling neurons. (PMID: 8930409, 1384763, 2479450) [HMDB] Biocytin is a naturally occurring low molecular weight analog of biotin, and a primary source of this essential metabolite for mammals. Biotinidase acts as a hydrolase by cleaving biocytin and biotinyl-peptides, thereby liberating biotin for reutilization. Mammals cannot synthesize biotin and, therefore, derive the vitamin from dietary sources or from the endogenous turnover of the carboxylases. Free biotin can readily enter the biotin pool, whereas holocarboxylases or other biotin-containing proteins must first be degraded proteolytically to biocytin (biotinyl-e-lysine) or biotinyl-peptides. Biocytin is also an especially versatile marker for neuroanatomical investigations, shown that may have multiple applications, especially for labeling neurons. (PMID:8930409, 1384763, 2479450).
L-Glutamine
Glutamine (Gln), also known as L-glutamine is an alpha-amino acid. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. Structurally, glutamine is similar to the amino acid glutamic acid. However, instead of having a terminal carboxylic acid, it has an amide. Glutamine is one of 20 proteinogenic amino acids, i.e., the amino acids used in the biosynthesis of proteins. Glutamine is found in all organisms ranging from bacteria to plants to animals. It is classified as an aliphatic, polar amino acid. In humans glutamine is considered a non-essential amino acid. Enzymatically, glutamine is formed by replacing a side-chain hydroxyl of glutamic acid with an amine functional group. More specifically, glutamine is synthesized by the enzyme glutamine synthetase from glutamate and ammonia. The most relevant glutamine-producing tissue are skeletal muscles, accounting for about 90\\\\\\% of all glutamine synthesized. Glutamine is also released, in small amounts, by the lungs and brain. In human blood, glutamine is the most abundant free amino acid. Dietary sources of glutamine include protein-rich foods such as beef, chicken, fish, dairy products, eggs, beans, beets, cabbage, spinach, carrots, parsley, vegetable juices, wheat, papaya, Brussels sprouts, celery and kale. Glutamine is one of the few amino acids that can directly cross the blood–brain barrier. Glutamine is often used as a supplement in weightlifting, bodybuilding, endurance and other sports, as well as by those who suffer from muscular cramps or pain, particularly elderly people. In 2017, the U.S. Food and Drug Administration (FDA) approved L-glutamine oral powder, marketed as Endari, to reduce severe complications of sickle cell disease in people aged five years and older with the disorder. Subjects who were treated with L-glutamine oral powder experienced fewer hospital visits for pain treated with a parenterally administered narcotic or ketorolac. The main use of glutamine within the diet of either group is as a means of replenishing the bodys stores of amino acids that have been used during exercise or everyday activities. Studies which have looked into problems with excessive consumption of glutamine thus far have proved inconclusive. However, normal supplementation is healthy mainly because glutamine is supposed to be supplemented after prolonged periods of exercise (for example, a workout or exercise in which amino acids are required for use) and replenishes amino acid stores. This is one of the main reasons glutamine is recommended during fasting or for people who suffer from physical trauma, immune deficiencies, or cancer. There is a significant body of evidence that links glutamine-enriched diets with positive intestinal effects. These include maintenance of gut barrier function, aiding intestinal cell proliferation and differentiation, as well as generally reducing septic morbidity and the symptoms of Irritable Bowel Syndrome (IBS). The reason for such "cleansing" properties is thought to stem from the fact that the intestinal extraction rate of glutamine is higher than that for other amino acids, and is therefore thought to be the most viable option when attempting to alleviate conditions relating to the gastrointestinal tract. These conditions were discovered after comparing plasma concentration within the gut between glutamine-enriched and non glutamine-enriched diets. However, even though glutamine is thought to have "cleansing" properties and effects, it is unknown to what extent glutamine has clinical benefits, due to the varied concentrations of glutamine in varieties of food. It is also known that glutamine has positive effects in reducing healing time after operations. Hospital waiting times after abdominal s... L-glutamine, also known as L-2-aminoglutaramic acid or levoglutamide, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. L-glutamine is soluble (in water) and a moderately acidic compound (based on its pKa). L-glutamine can be found in a number of food items such as acorn, yautia, ohelo berry, and oregon yampah, which makes L-glutamine a potential biomarker for the consumption of these food products. L-glutamine can be found primarily in most biofluids, including blood, sweat, breast milk, and cerebrospinal fluid (CSF), as well as throughout most human tissues. L-glutamine exists in all living species, ranging from bacteria to humans. In humans, L-glutamine is involved in several metabolic pathways, some of which include amino sugar metabolism, the oncogenic action of 2-hydroxyglutarate, mercaptopurine metabolism pathway, and transcription/Translation. L-glutamine is also involved in several metabolic disorders, some of which include the oncogenic action of d-2-hydroxyglutarate in hydroxygluaricaciduria, tay-sachs disease, xanthinuria type I, and adenosine deaminase deficiency. Moreover, L-glutamine is found to be associated with carbamoyl Phosphate Synthetase Deficiency, epilepsy, schizophrenia, and alzheimers disease. L-glutamine is a non-carcinogenic (not listed by IARC) potentially toxic compound. L-glutamine is a drug which is used for nutritional supplementation, also for treating dietary shortage or imbalance. L-Glutamine (L-Glutamic acid 5-amide) is a non-essential amino acid present abundantly throughout the body and involved in many metabolic processes. L-Glutamine provides a source of carbons for oxidation in some cells[1][2]. L-Glutamine (L-Glutamic acid 5-amide) is a non-essential amino acid present abundantly throughout the body and involved in many metabolic processes. L-Glutamine provides a source of carbons for oxidation in some cells[1][2]. L-Glutamine (L-Glutamic acid 5-amide) is a non-essential amino acid present abundantly throughout the body and involved in many metabolic processes. L-Glutamine provides a source of carbons for oxidation in some cells[1][2].
L-Arginine
Arginine (Arg), also known as L-argninine, belongs to the class of organic compounds known as L-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom. Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. L-asparagine is one of 20 proteinogenic amino acids, i.e., the amino acids used in the biosynthesis of proteins. Arginine is found in all organisms ranging from bacteria to plants to animals. Arginine is an essential amino acid that is physiologically active in the L-form. It is classified as a charged, basic, aliphatic amino acid. Arginine is considered to be a basic amino acid as it has a strongly basic guanidinium group. With a pKa of 12.48, the guanidinium group is positively charged in neutral, acidic, and even most basic environments. Because of the conjugation between the double bond and the nitrogen lone pairs, the positive charge is delocalized. This group is able to form multiple H-bonds. In mammals, arginine is formally classified as a semi-essential or conditionally essential amino acid, depending on the developmental stage and health status of the individual. Infants are unable to effectively synthesize arginine, making it nutritionally essential for infants. Adults, however, are able to synthesize arginine in the urea cycle. L-Arginine is an amino acid that has numerous functions in the body. It helps dispose of ammonia, is used to make compounds such as nitric oxide, creatine, L-glutamate, and L-proline, and it can be converted into glucose and glycogen if needed. Arginine also plays an important role in cell division, immunity and wound healing. Arginine is the immediate precursor of nitric oxide (NO), an important signaling molecule which can act as a second messenger, as well as an intercellular messenger which regulates vasodilation, and also has functions in the immune systems reaction to infection. Nitric oxide is made via the enzyme nitric oxide synthase (PMID 10690324). Arginine is also a precursor for several important nitrogen-containing compounds including urea, ornithine, and agmatine. Arginine is necessary for the synthesis of creatine and can be used for the synthesis of polyamines (mainly through ornithine and to a lesser degree through agmatine, citrulline, and glutamate.) The presence of asymmetric dimethylarginine (ADMA) in serum or plasma, a close relative of argninine, inhibits the nitric oxide synthase reaction. ADMA is considered a marker for vascular disease, just as L-arginine is considered a sign of a healthy endothelium. In large doses, L-arginine also stimulates the release of the hormones growth hormone and prolactin. Arginine is a known inducer of mTOR (mammalian target of rapamycin) and is responsible for inducing protein synthesis through the mTOR pathway. mTOR inhibition by rapamycin partially reduces arginine-induced protein synthesis (PMID: 20841502). Catabolic disease states such as sepsis, injury, and cancer cause an increase in arginine utilization, which can exceed normal body production, leading to arginine depletion. Arginine also activates AMP kinase (AMPK) which then stimulates skeletal muscle fatty acid oxidation and muscle glucose uptake, thereby increasing insulin secretion by pancreatic beta-cells (PMID: 21311355). Arginine is found in plant and animal proteins, such as dairy products, meat, poultry, fish, and nuts. The ratio of L-arginine to lysine is also important: soy and other plant proteins have more L-arginine than animal sources of protein. [Spectral] L-Arginine (exact mass = 174.11168) and L-Histidine (exact mass = 155.06948) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. L-Arginine. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=74-79-3 (retrieved 2024-06-29) (CAS RN: 74-79-3). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). L-Arginine ((S)-(+)-Arginine) is the substrate for the endothelial nitric oxide synthase (eNOS) to generate NO. L-Arginine is transported into vascular smooth muscle cells by the cationic amino acid transporter family of proteins where it is metabolized to nitric oxide (NO), polyamines, or L-proline[1][2]. L-Arginine ((S)-(+)-Arginine) is the substrate for the endothelial nitric oxide synthase (eNOS) to generate NO. L-Arginine is transported into vascular smooth muscle cells by the cationic amino acid transporter family of proteins where it is metabolized to nitric oxide (NO), polyamines, or L-proline[1][2].
Homocysteine
A high level of blood serum homocysteine is a powerful risk factor for cardiovascular disease. Unfortunately, one study which attempted to decrease the risk by lowering homocysteine was not fruitful. This study was conducted on nearly 5000 Norwegian heart attack survivors who already had severe, late-stage heart disease. No study has yet been conducted in a preventive capacity on subjects who are in a relatively good state of health.; Elevated levels of homocysteine have been linked to increased fractures in elderly persons. The high level of homocysteine will auto-oxidize and react with reactive oxygen intermediates and damage endothelial cells and has a higher risk to form a thrombus. Homocysteine does not affect bone density. Instead, it appears that homocysteine affects collagen by interfering with the cross-linking between the collagen fibers and the tissues they reinforce. Whereas the HOPE-2 trial showed a reduction in stroke incidence, in those with stroke there is a high rate of hip fractures in the affected side. A trial with 2 homocysteine-lowering vitamins (folate and B12) in people with prior stroke, there was an 80\\\\\\% reduction in fractures, mainly hip, after 2 years. Interestingly, also here, bone density (and the number of falls) were identical in the vitamin and the placebo groups.; Homocysteine is a sulfur-containing amino acid that arises during methionine metabolism. Although its concentration in plasma is only about 10 micromolar (uM), even moderate hyperhomocysteinemia is associated with increased incidence of cardiovascular disease and Alzheimers disease. Elevations in plasma homocysteine are commonly found as a result of vitamin deficiencies, polymorphisms of enzymes of methionine metabolism, and renal disease. Pyridoxal, folic acid, riboflavin, and Vitamin B(12) are all required for methionine metabolism, and deficiency of each of these vitamins result in elevated plasma homocysteine. A polymorphism of methylenetetrahydrofolate reductase (C677T), which is quite common in most populations with a homozygosity rate of 10-15 \\\\\\%, is associated with moderate hyperhomocysteinemia, especially in the context of marginal folate intake. Plasma homocysteine is inversely related to plasma creatinine in patients with renal disease. This is due to an impairment in homocysteine removal in renal disease. The role of these factors, and of modifiable lifestyle factors, in affecting methionine metabolism and in determining plasma homocysteine levels is discussed. Homocysteine is an independent cardiovascular disease (CVD) risk factor modifiable by nutrition and possibly exercise. Homocysteine was first identified as an important biological compound in 1932 and linked with human disease in 1962 when elevated urinary homocysteine levels were found in children with mental retardation. This condition, called homocysteinuria, was later associated with premature occlusive CVD, even in children. These observations led to research investigating the relationship of elevated homocysteine levels and CVD in a wide variety of populations including middle age and elderly men and women with and without traditional risk factors for CVD. (PMID 17136938, 15630149); Homocysteine is an amino acid with the formula HSCH2CH2CH(NH2)CO2H. It is a homologue of the amino acid cysteine, differing by an additional methylene (-CH2-) group. It is biosynthesized from methionine by the removal of its terminal C? methyl group. Homocysteine can be recycled into methionine or converted into cysteine with the aid of B-vitamins.; Studies reported in 2006 have shown that giving vitamins [folic acid, B6 and B12] to reduce homocysteine levels may not quickly offer benefit, however a significant 25\\\\\\% reduction in stroke was found in the HOPE-2 study even in patients mostly with existing serious arterial decline although the overall death rate was not significantly changed by the intervention in the trial. Clearly, reducing homocysteine does not quickly repair existing... Homocysteine (CAS: 454-29-5) is a sulfur-containing amino acid that arises during methionine metabolism. Although its concentration in plasma is only about 10 micromolar (uM), even moderate hyperhomocysteinemia is associated with an increased incidence of cardiovascular disease and Alzheimers disease. Elevations in plasma homocysteine are commonly found as a result of vitamin deficiencies, polymorphisms of enzymes of methionine metabolism, and renal disease. It has been identified as a uremic toxin according to the European Uremic Toxin Working Group (PMID: 22626821). Pyridoxal, folic acid, riboflavin, and vitamin B(12) are all required for methionine metabolism, and deficiency of each of these vitamins result in elevated plasma homocysteine. A polymorphism of methylenetetrahydrofolate reductase (C677T), which is quite common in most populations with a homozygosity rate of 10-15 \\\\\\%, is associated with moderate hyperhomocysteinemia, especially in the context of marginal folate intake. Plasma homocysteine is inversely related to plasma creatinine in patients with renal disease. This is due to an impairment in homocysteine removal in renal disease. The role of these factors, and of modifiable lifestyle factors, in affecting methionine metabolism and in determining plasma homocysteine levels is discussed. Homocysteine is an independent cardiovascular disease (CVD) risk factor modifiable by nutrition and possibly exercise. Homocysteine was first identified as an important biological compound in 1932 and linked with human disease in 1962 when elevated urinary homocysteine levels were found in children with mental retardation. This condition, called homocystinuria, was later associated with premature occlusive CVD, even in children. These observations led to research investigating the relationship of elevated homocysteine levels and CVD in a wide variety of populations including middle age and elderly men and women with and without traditional risk factors for CVD (PMID: 17136938 , 15630149). Moreover, homocysteine is found to be associated with cystathionine beta-synthase deficiency, cystathioninuria, methylenetetrahydrofolate reductase deficiency, and sulfite oxidase deficiency, which are inborn errors of metabolism. [Spectral] L-Homocysteine (exact mass = 135.0354) and L-Valine (exact mass = 117.07898) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Homocysteine is biosynthesized naturally via a multi-step process.[9] First, methionine receives an adenosine group from ATP, a reaction catalyzed by S-adenosyl-methionine synthetase, to give S-adenosyl methionine (SAM-e). SAM-e then transfers the methyl group to an acceptor molecule, (e.g., norepinephrine as an acceptor during epinephrine synthesis, DNA methyltransferase as an intermediate acceptor in the process of DNA methylation). The adenosine is then hydrolyzed to yield L-homocysteine. L-Homocysteine has two primary fates: conversion via tetrahydrofolate (THF) back into L-methionine or conversion to L-cysteine.[10] Biosynthesis of cysteine Mammals biosynthesize the amino acid cysteine via homocysteine. Cystathionine β-synthase catalyses the condensation of homocysteine and serine to give cystathionine. This reaction uses pyridoxine (vitamin B6) as a cofactor. Cystathionine γ-lyase then converts this double amino acid to cysteine, ammonia, and α-ketobutyrate. Bacteria and plants rely on a different pathway to produce cysteine, relying on O-acetylserine.[11] Methionine salvage Homocysteine can be recycled into methionine. This process uses N5-methyl tetrahydrofolate as the methyl donor and cobalamin (vitamin B12)-related enzymes. More detail on these enzymes can be found in the article for methionine synthase. Other reactions of biochemical significance Homocysteine can cyclize to give homocysteine thiolactone, a five-membered heterocycle. Because of this "self-looping" reaction, homocysteine-containing peptides tend to cleave themselves by reactions generating oxidative stress.[12] Homocysteine also acts as an allosteric antagonist at Dopamine D2 receptors.[13] It has been proposed that both homocysteine and its thiolactone may have played a significant role in the appearance of life on the early Earth.[14] L-Homocysteine. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=454-28-4 (retrieved 2024-06-29) (CAS RN: 6027-13-0). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). DL-Homocysteine is a weak neurotoxin, and can affect the production of kynurenic acid in the brain. DL-Homocysteine is a weak neurotoxin, and can affect the production of kynurenic acid in the brain. L-Homocysteine, a homocysteine metabolite, is a homocysteine that has L configuration. L-Homocysteine induces upregulation of cathepsin V that mediates vascular endothelial inflammation in hyperhomocysteinaemia[1][2].
L-2,4-diaminobutyric acid
L-3-Amino-isobutanoic acid is a component of branched-chain amino acid biosynthesis and metabolism. It can also be used in pyrimidine metabolism. L-3-Amino-isobutanoic acid is produced from S-methylmalonate semialdehyde by the enzyme 4-aminobutyrate aminotransferase. KEIO_ID D038 L-DABA (L-2,4-Diaminobutyric acid) is a week GABA transaminase inhibitor with an IC50 of larger than 500 μM; exhibits antitumor activity in vivo and in vitro. L-DABA (L-2,4-Diaminobutyric acid) is a week GABA transaminase inhibitor with an IC50 of larger than 500 μM; exhibits antitumor activity in vivo and in vitro.
Canavanine
L-Canavanine, a non-protein amino acid of certain leguminous plants, is related structurally to the protein amino acid, L-arginine. Canavanine is accumulated primarily in the seeds where it serves both as a defensive compound against herbivores and a vital source of nitrogen for the growing embryo. Organisms that consume it can mistakenly incorporate it into their own proteins, in the place of arginine thereby producing structurally aberrant proteins that may not function properly or not at all. Some specialized herbivores tolerate L-canavanine either because they metabolize it efficiently or avoid its incorporation into their own nascent proteins. Stored in large quantities in the seeds of leguminous plants in three subfamilies. Isol. originally from Jackbean (Canavalia ensiformis) KEIO_ID C094
3-Sulfinoalanine
3-Sulfinoalanine or cysteinesulfinic acid is a N-methyl-D-aspartate agonist. It is a product of cysteine dioxygenase or CDO [EC 1.13.11.20]. In humans cysteine catabolism is tightly regulated via regulation of cysteine dioxygenase (CDO) levels in the liver, with the turnover of CDO protein being dramatically decreased when intracellular cysteine levels increase. This occurs in response to changes in the intracellular cysteine concentration via changes in the rate of CDO ubiquitination and degradation. Expressed at high levels in the liver with lower levels in the kidney, brain, and lung, cysteine dioxygenase catalyzes the addition of molecular oxygen to the sulfhydryl group of cysteine, yielding cysteinesulfinic acid. The oxidative catabolism of cysteine to cysteinesulfinate by CDO represents an irreversible loss of cysteine from the free amino acid pool. Once generated, cysteinesulfinate is shuttled into several pathways including hypotaurine/taurine synthesis, sulfite/sulfate production, and the generation of pyruvate. [HMDB] 3-Sulfinoalanine or cysteinesulfinic acid is an N-methyl-D-aspartate agonist. It is a product of cysteine dioxygenase or CDO (EC 1.13.11.20). In humans, cysteine catabolism is tightly regulated via regulation of cysteine dioxygenase (CDO) levels in the liver, with the turnover of CDO protein being dramatically decreased when intracellular cysteine levels increase. This occurs in response to changes in the intracellular cysteine concentration via changes in the rate of CDO ubiquitination and degradation. Expressed at high levels in the liver with lower levels in the kidney, brain, and lung, cysteine dioxygenase catalyzes the addition of molecular oxygen to the sulfhydryl group of cysteine, yielding cysteinesulfinic acid. The oxidative catabolism of cysteine to cysteinesulfinate by CDO represents an irreversible loss of cysteine from the free amino acid pool. Once generated, cysteinesulfinate is shuttled into several pathways including hypotaurine/taurine synthesis, sulfite/sulfate production, and the generation of pyruvate. [Spectral] 3-Sulfino-L-alanine (exact mass = 153.00958) and L-Isoleucine (exact mass = 131.09463) and alpha-D-Glucose 6-phosphate (exact mass = 260.02972) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. [Spectral] 3-Sulfino-L-alanine (exact mass = 153.00958) and alpha-D-Glucose 6-phosphate (exact mass = 260.02972) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. [Spectral] 3-Sulfino-L-alanine (exact mass = 153.00958) and sn-Glycerol 3-phosphate (exact mass = 172.01367) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. KEIO_ID C015 L-Cysteinesulfinic acid is a potent agonist at several rat metabotropic glutamate receptors (mGluRs) with pEC50s of 3.92, 4.6, 3.9, 2.7, 4.0, and 3.94 for mGluR1, mGluR5, mGluR2, mGluR4, mGluR6, and mGluR8, respectively[1]. L-Cysteinesulfinic acid is a potent agonist at several rat metabotropic glutamate receptors (mGluRs) with pEC50s of 3.92, 4.6, 3.9, 2.7, 4.0, and 3.94 for mGluR1, mGluR5, mGluR2, mGluR4, mGluR6, and mGluR8, respectively[1].
L-Homoserine
L-homoserine, also known as 2-amino-4-hydroxybutanoic acid or isothreonine, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. L-homoserine is soluble (in water) and a moderately acidic compound (based on its pKa). L-homoserine can be found in common pea, which makes L-homoserine a potential biomarker for the consumption of this food product. L-homoserine can be found primarily in blood, feces, and urine, as well as in human prostate tissue. L-homoserine exists in all living species, ranging from bacteria to humans. In humans, L-homoserine is involved in the methionine metabolism. L-homoserine is also involved in several metabolic disorders, some of which include glycine n-methyltransferase deficiency, hypermethioninemia, cystathionine beta-synthase deficiency, and methylenetetrahydrofolate reductase deficiency (MTHFRD). Homoserine (also called isothreonine) is an α-amino acid with the chemical formula HO2CCH(NH2)CH2CH2OH. L-Homoserine is not one of the common amino acids encoded by DNA. It differs from the proteinogenic amino acid serine by insertion of an additional -CH2- unit into the backbone. Homoserine, or its lactone form, is the product of a cyanogen bromide cleavage of a peptide by degradation of methionine . Homoserine is a more reactive variant of the amino acid serine. In this variant, the hydroxyl side chain contains an additional CH2 group which brings the hydroxyl group closer to its own carboxyl group, allowing it to chemically react to form a five-membered ring. This occurs at the point that amino acids normally join to their neighbours in a peptide bond. Homoserine is therefore unsuitable for forming proteins and has been eliminated from the repertoire of amino acids used by living things. Homoserine is the final product on the C-terminal end of the N-terminal fragment following a cyanogen bromide cleavage. (wikipedia). Homoserine is also a microbial metabolite. L-Homoserine. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=672-15-1 (retrieved 2024-07-02) (CAS RN: 672-15-1). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). L-Homoserine is a non - protein amino acid, which is an important biosynthetic intermediate of threonine, methionine and lysine. L-Homoserine is a non - protein amino acid, which is an important biosynthetic intermediate of threonine, methionine and lysine.
L-Lysine
Lysine (Lys), also known as L-lysine is an alpha-amino acid. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. Lysine is one of 20 proteinogenic amino acids, i.e., the amino acids used in the biosynthesis of proteins. Lysine is found in all organisms ranging from bacteria to plants to animals. It is classified as an aliphatic, positively charged or basic amino acid. In humans, lysine is an essential amino acid, meaning the body cannot synthesize it, and it must be obtained from the diet. Lysine is high in foods such as wheat germ, cottage cheese and chicken. Of meat products, wild game and pork have the highest concentration of lysine. Fruits and vegetables contain little lysine, except avocados. Normal requirements for lysine have been found to be about 8 g per day or 12 mg/kg in adults. Children and infants need more, 44 mg/kg per day for an eleven to-twelve-year old, and 97 mg/kg per day for three-to six-month old. In organisms that synthesise lysine, it has two main biosynthetic pathways, the diaminopimelate and α-aminoadipate pathways, which employ distinct enzymes and substrates and are found in diverse organisms. Lysine catabolism occurs through one of several pathways, the most common of which is the saccharopine pathway. Lysine plays several roles in humans, most importantly proteinogenesis, but also in the crosslinking of collagen polypeptides, uptake of essential mineral nutrients, and in the production of carnitine, which is key in fatty acid metabolism. Lysine is also often involved in histone modifications, and thus, impacts the epigenome. Lysine is highly concentrated in muscle compared to most other amino acids. Normal lysine metabolism is dependent upon many nutrients including niacin, vitamin B6, riboflavin, vitamin C, glutamic acid and iron. Excess arginine antagonizes lysine. Several inborn errors of lysine metabolism are known, such as cystinuria, hyperdibasic aminoaciduria I, lysinuric protein intolerance, propionic acidemia, and tyrosinemia I. Most are marked by mental retardation with occasional diverse symptoms such as absence of secondary sex characteristics, undescended testes, abnormal facial structure, anemia, obesity, enlarged liver and spleen, and eye muscle imbalance. Lysine also may be a useful adjunct in the treatment of osteoporosis. Although high protein diets result in loss of large amounts of calcium in urine, so does lysine deficiency. Lysine may be an adjunct therapy because it reduces calcium losses in urine. Lysine deficiency also may result in immunodeficiency. Requirements for lysine are probably increased by stress. Lysine toxicity has not occurred with oral doses in humans. Lysine dosages are presently too small and may fail to reach the concentrations necessary to prove potential therapeutic applications. Lysine metabolites, amino caproic acid and carnitine have already shown their therapeutic potential. Thirty grams daily of amino caproic acid has been used as an initial daily dose in treating blood clotting disorders, indicating that the proper doses of lysine, its precursor, have yet to be used in medicine. Low lysine levels have been found in patients with Parkinsons, hypothyroidism, kidney disease, asthma and depression. The exact significance of these levels is unclear, yet lysine therapy can normalize the level and has been associated with improvement of some patients with these conditions. Abnormally elevated hydroxylysines have been found in virtually all chronic degenerative diseases and those treated with coumadin therapy. The levels of this stress marker may be improved by high doses of vitamin C. Lysine is particularly useful in therapy for marasmus (wasting) (http://www.dcnutrition.com). Lysine has also been sh... [Spectral] L-Lysine (exact mass = 146.10553) and Carnosine (exact mass = 226.10659) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Dietary supplement, nutrient. Found widely in protein hydrolysates, e.g. casein, egg albumen, fibrin, gelatin, beet molasses. Flavouring agent for a variety of foods L-Lysine. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=56-87-1 (retrieved 2024-07-01) (CAS RN: 56-87-1). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). L-lysine is an essential amino acid[1][2] with important roles in connective tissues and carnitine synthesis, energy production, growth in children, and maintenance of immune functions[2]. L-lysine is an essential amino acid[1][2] with important roles in connective tissues and carnitine synthesis, energy production, growth in children, and maintenance of immune functions[2].
Methionine sulfoxide
Methionine sulfoxide belongs to the class of organic compounds known as l-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom. Methionine sulfoxide exists in all living species, ranging from bacteria to humans. Within humans, methionine sulfoxide participates in a number of enzymatic reactions. In particular, methionine sulfoxide can be biosynthesized from L-methionine through its interaction with the enzyme methionine-R-sulfoxide reductase B3. In addition, methionine sulfoxide can be biosynthesized from L-methionine through the action of the enzyme methionine-R-sulfoxide reductase b2, mitochondrial. In humans, methionine sulfoxide is involved in the metabolic disorder called hypermethioninemia. Methionine sulfoxide is an oxidation product of methionine with reactive oxygen species via 2-electron-dependent mechanism. Such oxidants can be generated from activated neutrophils; therefore, methionine sulfoxide can be regarded as a biomarker of oxidative stress in vivo. (PMID 12576054) [HMDB]. Methionine sulfoxide is found in many foods, some of which are romaine lettuce, white cabbage, dill, and yellow bell pepper. L-Methionine sulfoxide (H-Met(O)-OH), a metabolite of Methionine, induces M1/classical macrophage polarization, and modulates oxidative stress and purinergic signaling parameters[1]. Methionine sulfoxide is an oxidation product of methionine with reactive oxygen species and can be regarded as a biomarker of oxidative stress in vivo. Methionine sulfoxide is an oxidation product of methionine with reactive oxygen species and can be regarded as a biomarker of oxidative stress in vivo.
Nα-Acetyl-L-lysine
N-epsilon-Acetyl-L-lysine also known as Nepsilon-Acetyllysine or N6-Acetyllysine, belongs to the class of organic compounds known as N-acyl-alpha amino acids. N-acyl-alpha amino acids are compounds containing an alpha amino acid which bears an acyl group at one of its nitrogen atoms. N-epsilon-Acetyl-L-lysine can also be classified as an alpha amino acid or a derivatized alpha amino acid. Technically, N-epsilon-Acetyl-L-lysine is a biologically available sidechain, N-capped form of the proteinogenic alpha amino acid L-lysine. Unlike L-lysine, acetylated lysine derivatives such as N-epsilon-Acetyl-L-lysine are zwitterionic compounds. These are molecules that contains an equal number of positively- and negatively-charged functional groups. N-epsilon-Acetyl-L-lysine is found naturally in eukaryotes ranging from yeast to plants to humans. N-acetyl amino acids can be produced either via direct synthesis of specific N-acetyltransferases or via the proteolytic degradation of N-acetylated proteins (often histones) by specific hydrolases. N-epsilon-Acetyl-L-lysine can be biosynthesized from L-lysine and acetyl-CoA via the enzyme known as Lysine N-acetyltransferase. Post-translational lysine-acetylation is one of two major modifications of lysine residues in various proteins – either N-terminal or N-alpha acetylation or N6 (sidechain) acetylation. Side-chain acetylation of specific lysine residues in the N-terminal domains of core histones is a biochemical marker of active genes. Acetylation is now known to play a major role in eukaryotic transcription. Specifically, acetyltransferase enzymes that act on particular lysine side chains of histones and other proteins are intimately involved in transcriptional activation. By modifying chromatin proteins and transcription-related factors, these acetylases are believed to regulate the transcription of many genes. The best-characterized mechanism is acetylation, catalyzed by histone acetyltransferase (HAT) enzymes. HATs function enzymatically by transferring an acetyl group from acetyl-coenzyme A (acetyl-CoA) to the amino group of certain lysine side chains within a histones basic N-terminal tail region. Within a histone octamer, these regions extend out from the associated globular domains, and in the context of a nucleosome, they are believed to bind the DNA through charge interactions (positively charged histone tails associated with negatively charged DNA) or mediate interactions between nucleosomes. Lysine acetylation, which neutralizes part of a tail regions positive charge, is postulated to weaken histone-DNA or nucleosome-nucleosome interactions and/or signal a conformational change, thereby destabilizing nucleosome structure or arrangement and giving other nuclear factors, such as the transcription complex, more access to a genetic locus. In agreement with this is the fact that acetylated chromatin has long been associated with states of transcriptional activation. Specific recognition of N6-acetyl-L-lysine is a conserved function of all bromodomains found in different proteins, recognized as an emerging intracellular signalling mechanism that plays critical roles in regulating gene transcription, cell-cycle progression, apoptosis, DNA repair, and cytoskeletal organization (PMID: 9169194 , 10827952 , 17340003 , 16247734 , 9478947 , 10839822 ). N-acetylated amino acids, such as N-epsilon-Acetyl-L-lysine can be released by an N-acylpeptide hydrolase from histones going through proteolytic degradation (PMID: 16465618). Many N-acetylamino acids are classified as uremic toxins if present in high abundance in the serum or plasma (PMID: 26317986; PMID: 20613759). Uremic toxins are a diverse group of endogenously produced molecules that, if not properly cleared or eliminated by the kidneys, can cause kidney damage, cardiovascular disease and neurological deficits (PMID: 18287557). Isolated from sugarbeet (Beta vulgaris) KEIO_ID A174 Nepsilon-Acetyl-L-lysine is a derivative of the amino acid lysine.
O-Acetylserine
O-Acetylserine is an α-amino acid with the chemical formula HO2CCH(NH2)CH2OC(O)CH3. It is an intermediate in the biosynthesis of the common amino acid cysteine in bacteria and plants. O-Acetylserine is biosynthesized by acetylation of the serine by the enzyme serine transacetylase. The enzyme O-acetylserine (thiol)-lyase, using sulfide sources, converts this ester into cysteine, releasing acetate. O-Acetylserine belongs to the class of organic compounds known as l-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom. O-Acetylserine (OASS) is an acylated amino acid derivative. O-Acetylserine exists in all living species, ranging from bacteria to humans. Outside of the human body, O-Acetylserine has been detected, but not quantified in several different foods, such as okra, vaccinium (blueberry, cranberry, huckleberry), rapes, sparkleberries, and lingonberries. This could make O-acetylserine a potential biomarker for the consumption of these foods. O-acetyl-l-serine, also known as L-serine, acetate (ester) or (2s)-3-acetyloxy-2-aminopropanoate, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. O-acetyl-l-serine is soluble (in water) and a moderately acidic compound (based on its pKa). O-acetyl-l-serine can be found in a number of food items such as sorrel, summer savory, purslane, and cherimoya, which makes O-acetyl-l-serine a potential biomarker for the consumption of these food products. O-acetyl-l-serine can be found primarily in blood and urine, as well as in human prostate tissue. O-acetyl-l-serine exists in all living species, ranging from bacteria to humans. Acquisition and generation of the data is financially supported in part by CREST/JST. O-Acetylserine (O-Acetyl-L-serine) is an intermediate in the biosynthesis of the amino acid cysteine in bacteria and plants.
L-Ornithine
Ornithine, also known as (S)-2,5-diaminopentanoic acid or ornithine, (L)-isomer, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. Ornithine is soluble (in water) and a moderately acidic compound (based on its pKa). Ornithine can be found in a number of food items such as pine nut, lingonberry, turnip, and cassava, which makes ornithine a potential biomarker for the consumption of these food products. Ornithine can be found primarily in most biofluids, including urine, cerebrospinal fluid (CSF), feces, and saliva, as well as throughout most human tissues. Ornithine exists in all living species, ranging from bacteria to humans. In humans, ornithine is involved in few metabolic pathways, which include arginine and proline metabolism, glycine and serine metabolism, spermidine and spermine biosynthesis, and urea cycle. Ornithine is also involved in several metabolic disorders, some of which include ornithine transcarbamylase deficiency (OTC deficiency), prolidase deficiency (PD), citrullinemia type I, and arginine: glycine amidinotransferase deficiency (AGAT deficiency). Moreover, ornithine is found to be associated with cystinuria, alzheimers disease, leukemia, and uremia. Ornithine is a non-carcinogenic (not listed by IARC) potentially toxic compound. Ornithine is a drug which is used for nutritional supplementation, also for treating dietary shortage or imbalance. it has been claimed that ornithine improves athletic performance, has anabolic effects, has wound-healing effects, and is immuno-enhancing. Ornithine is a non-proteinogenic amino acid that plays a role in the urea cycle. Ornithine is abnormally accumulated in the body in ornithine transcarbamylase deficiency. The radical is ornithyl . L-Ornithine is metabolised to L-arginine. L-arginine stimulates the pituitary release of growth hormone. Burns or other injuries affect the state of L-arginine in tissues throughout the body. As De novo synthesis of L-arginine during these conditions is usually not sufficient for normal immune function, nor for normal protein synthesis, L-ornithine may have immunomodulatory and wound-healing activities under these conditions (by virtue of its metabolism to L-arginine) (DrugBank). Chronically high levels of ornithine are associated with at least 9 inborn errors of metabolism including: Cystathionine Beta-Synthase Deficiency, Hyperornithinemia with gyrate atrophy, Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome, Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome, Hyperprolinemia Type II, Lysinuric Protein Intolerance, Ornithine Aminotransferase Deficiency, Ornithine Transcarbamylase Deficiency and Prolinemia Type II (T3DB). Ornithine or L-ornithine, also known as (S)-2,5-diaminopentanoic acid is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. L-ornithine is soluble (in water) and a moderately basic compound. Ornithine is a non-proteinogenic amino acid that plays a role in the urea cycle. It is considered to be a non-essential amino acid. A non-essential amino acid is an amino acid that can be synthesized from central metabolic pathway intermediates in humans and is not required in the diet. L-Ornithine is one of the products of the action of the enzyme arginase on L-arginine, creating urea. Therefore, ornithine is a central part of the urea cycle, which allows for the disposal of excess nitrogen. Outside the human body, L-ornithine is abundant in a number of food items such as wild rice, brazil nuts, common oregano, and common grapes. L-ornithine can be found throughout most human tissues; and in most biofluids, some of which include blood, urine, cerebrospinal fluid (CSF), sweat, saliva, and feces. L-ornithine exists in all living species, from bacteria to plants to humans. L-Ornithine is also a precursor of citrulline and arginine. In order for ornithine that is produced in the cytosol to be converted to citrulline, it must first cross the inner mitochondrial membrane into the mitochondrial matrix where it is carbamylated by the enzyme known as ornithine transcarbamylase. This transfer is mediated by the mitochondrial ornithine transporter (SLC25A15; AF112968; ORNT1). Mutations in the mitochondrial ornithine transporter result in hyperammonemia, hyperornithinemia, homocitrullinuria (HHH) syndrome, a disorder of the urea cycle (PMID: 16256388). The pathophysiology of the disease may involve diminished ornithine transport into mitochondria, resulting in ornithine accumulation in the cytoplasm and reduced ability to clear carbamoyl phosphate and ammonia loads (OMIM 838970). In humans, L-ornithine is involved in a number of other metabolic disorders, some of which include, ornithine transcarbamylase deficiency (OTC deficiency), argininemia, and guanidinoacetate methyltransferase deficiency (GAMT deficiency). Ornithine is abnormally accumulated in the body in ornithine transcarbamylase deficiency. Moreover, Ornithine is found to be associated with cystinuria, hyperdibasic aminoaciduria I, and lysinuric protein intolerance, which are inborn errors of metabolism. It has been claimed that ornithine improves athletic performance, has anabolic effects, has wound-healing effects, and is immuno-enhancing. L-Ornithine. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=70-26-8 (retrieved 2024-07-01) (CAS RN: 70-26-8). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). L-Ornithine ((S)-2,5-Diaminopentanoic acid) is a non-proteinogenic amino acid, is mainly used in urea cycle removing excess nitrogen in vivo. L-Ornithine shows nephroprotective[1][2]. L-Ornithine ((S)-2,5-Diaminopentanoic acid) is a non-proteinogenic amino acid, is mainly used in urea cycle removing excess nitrogen in vivo. L-Ornithine shows nephroprotective[1][2].
Norfloxacin
Norfloxacin is only found in individuals that have used or taken this drug. It is a synthetic fluoroquinolone (fluoroquinolones) with broad-spectrum antibacterial activity against most gram-negative and gram-positive bacteria. Norfloxacin inhibits bacterial DNA gyrase. [PubChem]The bactericidal action of Norfloxacin results from inhibition of the enzymes topoisomerase II (DNA gyrase) and topoisomerase IV, which are required for bacterial DNA replication, transcription, repair, and recombination. Norfloxacin is a broad-spectrum antibiotic that is active against both gram-positive and gram-negative bacterias. The fluorine atom at the 6 position increases potency against gram-negative organisms, and the piperazine moiety at the 7 position is responsible for anti-pseudomonal activity J - Antiinfectives for systemic use > J01 - Antibacterials for systemic use > J01M - Quinolone antibacterials > J01MA - Fluoroquinolones D004791 - Enzyme Inhibitors > D065607 - Cytochrome P-450 Enzyme Inhibitors > D065609 - Cytochrome P-450 CYP1A2 Inhibitors D000970 - Antineoplastic Agents > D059003 - Topoisomerase Inhibitors > D059005 - Topoisomerase II Inhibitors S - Sensory organs > S01 - Ophthalmologicals > S01A - Antiinfectives > S01AE - Fluoroquinolones D000890 - Anti-Infective Agents > D000900 - Anti-Bacterial Agents > D024841 - Fluoroquinolones C254 - Anti-Infective Agent > C258 - Antibiotic > C795 - Quinolone Antibiotic CONFIDENCE standard compound; EAWAG_UCHEM_ID 232 CONFIDENCE standard compound; INTERNAL_ID 1032
Diaminopimelic acid
Diaminopimelic acid or DAPA is a lysine-like amino acid derivative that is a key component of the bacterial cell wall. DAPA is incorporated or integrated into peptidoglycan of gram negative bacteria and is the attachment point for Brauns lipoprotein (BLP or Murein Lipoprotein). BLP is found in gram-negative cell walls and is one of the most abundant membrane proteins. BLP is bound at its C-terminal end (a lysine) by a covalent bond to the peptidoglycan layer (specifically to diaminopimelic acid molecules) and is embedded in the outer membrane by its hydrophobic head (a cysteine with lipids attached). BLP tightly links the two layers and provides structural integrity to the bacterial outer membrane. Diaminopimelic acid can be found in human urine or feces due to the lysis or enzymatic breakdown of gram negative gut microbes. Acquisition and generation of the data is financially supported in part by CREST/JST. 2,6-Diaminoheptanedioic acid is an endogenous metabolite.
L-Norleucine
L-Norleucine, also known as L-aminohexanoate or caprine, belongs to the class of organic compounds known as l-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom. Thus, L-norleucine is considered to be a fatty acid lipid molecule. An unnatural amino acid that is used experimentally to study protein structure and function. L-Norleucine is a very hydrophobic molecule, practically insoluble in water, and relatively neutral. L-Norleucine exists in all eukaryotes, ranging from yeast to humans. Outside of the human body, L-Norleucine has been detected, but not quantified in cow milk. This could make L-norleucine a potential biomarker for the consumption of these foods. It binds reversibly to the kringle domain of plasminogen and blocks the binding of plasminogen to fibrin and its activation to plasmin. An unnatural amino acid that is used experimentally to study protein structure and function. It is structurally similar to methionine, however it does not contain sulfur. Acquisition and generation of the data is financially supported in part by CREST/JST. CONFIDENCE standard compound; INTERNAL_ID 22 KEIO_ID N014 L-Norleucine ((S)-2-Aminohexanoic acid) is an isomer of leucine, specifically affects protein synthesis in skeletal muscle, and has antivirus activity.
Citrulline
Citrulline, also known as Cit or δ-ureidonorvaline, belongs to the class of organic compounds known as l-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom. Citrulline has the formula H2NC(O)NH(CH2)3CH(NH2)CO2H. Citrulline exists in all living species, ranging from bacteria to humans. Within humans, citrulline participates in a number of enzymatic reactions. In particular, citrulline can be biosynthesized from carbamoyl phosphate and ornithine which is catalyzed by the enzyme ornithine carbamoyltransferase. In addition, citrulline and L-aspartic acid can be converted into argininosuccinic acid through the action of the enzyme argininosuccinate synthase. In humans, citrulline is involved in the metabolic disorder called argininemia. Citrulline has also been found to be associated with several diseases such as ulcerative colitis, rheumatoid arthritis, and citrullinemia type II. Citrulline has also been linked to several inborn metabolic disorders including argininosuccinic aciduria and fumarase deficiency. Outside of the human body, citrulline is found, on average, in the highest concentration in a few different foods such as wheats, oats, and cucumbers and in a lower concentration in swiss chards, yellow wax beans, and potato. Citrulline has also been detected, but not quantified in several different foods, such as epazotes, lotus, common buckwheats, strawberry guava, and italian sweet red peppers. Citrulline is a potentially toxic compound. Proteins that normally contain citrulline residues include myelin basic protein (MBP), filaggrin, and several histone proteins, whereas other proteins, such as fibrin and vimentin are susceptible to citrullination during cell death and tissue inflammation. Citrulline is also produced as a byproduct of the enzymatic production of nitric oxide from the amino acid arginine, catalyzed by nitric oxide synthase. It is also produced from arginine as a byproduct of the reaction catalyzed by NOS family (NOS; EC1.14.13.39). [Spectral] L-Citrulline (exact mass = 175.09569) and L-Glutamate (exact mass = 147.05316) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Acquisition and generation of the data is financially supported in part by CREST/JST. COVID info from clinicaltrial, clinicaltrials, clinical trial, clinical trials Occurs in the juice of watermelon (Citrullus vulgaris) IPB_RECORD: 257; CONFIDENCE confident structure KEIO_ID C013 Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS 2-Amino-5-ureidopentanoic acid is an endogenous metabolite. 2-Amino-5-ureidopentanoic acid is an endogenous metabolite. L-Citrulline is an amino acid derived from ornithine in the catabolism of proline or glutamine and glutamate, or from l-arginine via arginine-citrulline pathway. L-Citrulline is an amino acid derived from ornithine in the catabolism of proline or glutamine and glutamate, or from l-arginine via arginine-citrulline pathway.
(S)-Homostachydrine
(S)-Homostachydrine (also known as pipecolic acid betaine or homostachydrine) can be found in green coffee beans of Robusta and Arabica species (PMID: 27006213). (S)-Homostachydrine content is unaffected by coffee bean roasting treatment because of its remarkable heat stability. This makes it a good candidate marker for determining the content of Robusta and Arabica species in roasted coffee blends. (S)-Homostachydrine is also a potential marker of coffee consumption as it can be found in both human serum and human urine. It is also found in alfalfa seeds and leaves. More specifically, (S)-homostachydrine can be isolated from the seeds of Medicago sativa (alfalfa) as well as from Achillea millefolium (yarrow). (S)-Homostachydrine is also found in the fruits, seeds, and leaves of orange, lemon, and bergamot (PMID: 22208890). Isolated from seeds of Medicago sativa (alfalfa)and is also from Achillea millefolium (yarrow). (S)-Homostachydrine is found in alfalfa, herbs and spices, and pulses.
Ectoine
Ectoine belongs to the class of organic compounds known as alpha-amino acids. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Ectoine has been identified in urine (PMID: 22409530). CONFIDENCE standard compound; ML_ID 37 C26170 - Protective Agent KEIO_ID E011 Ectoine is a natural cell protectant, an amino acid derivate produced by bacteria living under extremely harsh environmental conditions. Ectoine serves as an osmoregulatory compatible solute, increasing the hydration of the skin surface and stabilizing lipid layers, which is useful in skincare. Ectoine demonstrates a good safety profile for the treatment of allergic rhinitis[1][2].
Homo-L-arginine
L-homoarginine, also known as N6-(aminoiminomethyl)-L-lysine or N6-amidino-L-lysine, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. More specifically, L-homoarginine is a naturally occurring, non-proteinogenic, cationic amino acid. It is formed in the liver in a reaction catalyzed by L-arginine:glycine amidinotransferase (AGAT) when transferring the amidino group from arginine to lysine. It is an alternative substrate for nitric oxide (NO) synthase. L-homoarginine increases the availability of NO and thereby affects endothelial function. High homoarginine levels may exert positive actions that are relevant to cardiovascular health, including enhanced endothelial function, inhibition of platelet aggregation and stimulation of insulin secretion (PMID: 30866658). Recent studies have demonstrated that low serum homoarginine levels are a strong predictor of cardiovascular mortality (PMID: 24583919). L-homoarginine is a substrate of the human cationic amino acid CAT1 [solute carrier family 7 (SLC7A1)], CAT2A (SLC7A2A) or CAT2B (SLC7A2B) (PMID: 28684763). According to published human metabolomic data, L-homoarginine can be found primarily in blood, cerebrospinal fluid (CSF), and urine, as well as in human intestinal and testes tissues. Moreover, L-homoarginine has been found to be associated with liver cirrhosis and the genetic disorder, hyperargininemia. Homoarginine is an organ-specific uncompetitive inhibitor of human liver and bone alkaline phosphohydrolase (PMID: 5063678). H-HoArg-OH, a homologue arginine, is a strong inhibitor of human bone and liver alkaline phosphatase.
N(6)-Methyllysine
N(6)-Methyllysine is a naturally occurring amino acid found in human biofluids. N-monomethyl-lysine is generated by metabolic transmethylation of endogenous lysine. Lysine methylation displays the highest degree of complexity among known covalent histone modifications, with each site of methylation regulating the association of different effector molecules. The versatility of lysine methylation marks is perhaps best exemplified by modifications implicated in transcriptional regulation as well as being required for double-strand break repair in several organisms. Identification of the numerous biological functions encoded by histone lysine methylation is a major area of research interest, as these mechanisms are intimately associated with cellular senescence, genomic instability, and leukemogenesis. While multiple sites of lysine methylation have been linked with gene activation, each modification is distributed to unique positions across the active gene. (PMID: 17030614, 1122639, 15756599, 3111294). N(6)-Methyllysine is a naturally occurring amino acid found in human biofluids. N-monomethyl-lysine is generated by metabolic transmethylation of endogenous lysine.
Phosphoserine
The phosphoric acid ester of serine. As a constituent (residue) of proteins, its side chain can undergo O-linked glycosylation. This might be important in explaining some of the devastating consequences of diabetes. It is one of three amino acid residues that are commonly phosphorylated by kinases during cell signalling in eukaryotes. Phosphorylated serine residues are often referred to as phosphoserine. Serine proteases are a common type of protease. Serine, organic compound, one of the 20 amino acids commonly found in animal proteins. Only the L-stereoisomer appears in mammalian protein. It is not essential to the human diet, since it can be synthesized in the body from other metabolites, including glycine. Serine was first obtained from silk protein, a particularly rich source, in 1865. Its name is derived from the Latin for silk, sericum. Serines structure was established in 1902. [HMDB] Phosphoserine is the phosphoric acid ester of the amino acid serine. It is found in essentially all living organisms ranging from microbes to plants to mammals. Phosphoserine is a component of many proteins as the result of posttranslational modifications to the native protein’s serine residue(s). The phosphorylation of the hydroxyl functional group in serine to produce phosphoserine is catalyzed by various types of kinases. Serine is one of three amino acid residues that are commonly phosphorylated by kinases during cell signalling in eukaryotes. Free phosphoserine is found in many biofluids and likely arises from the proteolysis of proteins containing phosphoserine residues (PMID: 7693088). Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID P060 DL-O-Phosphoserine, a normal metabolite in human biofluid, is an ester of serine and phosphoric acid.
O-Phosphothreonine
Phosphothreonine is a phosphoamino acid. It is the phosphorylated ester of threonine. There are three amino acids that are typically phosphorylated in eukaryotes: serine, threonine, and tyrosine. Threonine residues in endogenous proteins undergo phosphorylation through the action of a threonine kinase. Small amounts of free phosphothreonine can be detected in urine [PMID: 7693088]. [HMDB] Phosphothreonine is a phosphoamino acid. It is the phosphorylated ester of threonine. There are three amino acids that are typically phosphorylated in eukaryotes: serine, threonine, and tyrosine. Threonine residues in endogenous proteins undergo phosphorylation through the action of a threonine kinase. Small amounts of free phosphothreonine can be detected in urine [PMID: 7693088]. D019995 - Laboratory Chemicals > D007202 - Indicators and Reagents
L-3-Cyanoalanine
3-cyano-l-alanine, also known as L-beta-cyanoalanine or 3-cyanoalanine, (D)-isomer, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. 3-cyano-l-alanine is soluble (in water) and an extremely strong acidic compound (based on its pKa). 3-cyano-l-alanine can be found in a number of food items such as conch, abiyuch, rubus (blackberry, raspberry), and lemon thyme, which makes 3-cyano-l-alanine a potential biomarker for the consumption of these food products. 3-cyano-l-alanine exists in all living organisms, ranging from bacteria to humans. L-3-Cyanoalanine, also known as L-beta-cyanoalanine, belongs to the class of organic compounds known as L-alpha-amino acids. These are alpha-amino acids which have the L-configuration of the alpha-carbon atom. L-3-Cyanoalanine is a very strong basic compound (based on its pKa). L-3-Cyanoalanine exists in all living organisms, ranging from bacteria to humans. Outside of the human body, L-3-cyanoalanine has been detected, but not quantified in, several different foods, such as summer savouries, orange bell peppers, red rices, mixed nuts, and green bell peppers. This could make L-3-cyanoalanine a potential biomarker for the consumption of these foods.
(2E)-Decenoyl-ACP
(2E)-Decenoyl-ACP, also known as Cycloleucine or 1-Aminocyclopentanecarboxylic acid, is classified as a member of the L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. (2E)-Decenoyl-ACP is considered to be soluble (in water) and acidic Acquisition and generation of the data is financially supported in part by CREST/JST. C308 - Immunotherapeutic Agent > C574 - Immunosuppressant KEIO_ID A050
L-Homocysteic acid
L-homocysteic acid is a homocysteic acid with L-configuration. It has a role as a NMDA receptor agonist. It is an enantiomer of a D-homocysteic acid. L-Homocysteic acid is a sulfur-containing glutamic acid analog and a potent NMDA receptor agonist. It is related to homocysteine, a by-product of methionine metabolism. It belongs to the class of organic compounds known as l-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom. Short-term incubation of lymphocytes with homocysteine or its oxidation product homocysteinic acid increased the formation of reactive oxygen species and cell necrosis [HMDB]
Homocitrulline
Homocitrulline is a metabolite that can be detected in larger amounts in the urine of individuals with urea cycle disorders (OMIM 238970). The accumulation of carbamylphosphate due to depleted supply of ornithine for the urea cycle may be responsible for the enhanced synthesis of homocitrulline and homoarginine in some cases (PMID 2474087). Homocitrulline has been identified in the human placenta (PMID: 32033212). Homocitrulline is a metabolite that can be detected in larger amounts in the urine of individuals with urea cycle disorders (OMIM 238970). The accumulation of carbamylphosphate due to depleted supply of ornithine for the urea cycle may be responsible for the enhanced synthesis of homocitrulline and homoarginine in some cases (PMID 2474087). [HMDB] L-Homocitrulline is metabolized to homoarginine through homoargininosuccinate via the urea cycle pathway and its metabolic abnormality could lead to Lysinuric Protein Intolerance (LPI). L-Homocitrulline is metabolized to homoarginine through homoargininosuccinate via the urea cycle pathway and its metabolic abnormality could lead to Lysinuric Protein Intolerance (LPI).
N6,N6,N6-Trimethyl-L-lysine
N6,N6,N6-Trimethyl-L-lysine is a methylated derivative of the amino acid lysine. It is a component of histone proteins, a precursor of carnitine and a coenzyme of fatty acid oxidation. N6,N6,N6-Trimethyl-L-lysine residues are found in a number of proteins and are generated by the action of S-adenosyl-L-methionine on exposed lysine residues. When trimethyllysine is released from cognate proteins via proteolysis, it serves as a precursor for carnitine biosynthesis. Mitochondrial 6-N-trimethyllysine dioxygenase converts 6-N-trimethyllysine to 3-hydroxy-6-N-trimethyllysine as the first step for carnitine biosynthesis. Because the subsequent carnitine biosynthesis enzymes are cytosolic, 3-hydroxy-6-N-trimethyllysine must be transported out of the mitochondria by a putative mitochondrial 6-N-trimethyllysine/3-hydroxy-6-N-trimethyllysine transporter system. Plasma -N-trimethyllysine concentrations are significantly lower in systemic carnitine deficiency patients compared to normal individuals, but no significant difference in urinary -N-trimethyllysine excretion is seen between the two groups. [HMDB] N6,N6,N6-Trimethyl-L-lysine is a methylated derivative of the amino acid lysine. It is a component of histone proteins, a precursor of carnitine and a coenzyme of fatty acid oxidation. N6,N6,N6-Trimethyl-L-lysine residues are found in a number of proteins and are generated by the action of S-adenosyl-L-methionine on exposed lysine residues. When trimethyllysine is released from cognate proteins via proteolysis, it serves as a precursor for carnitine biosynthesis. Mitochondrial 6-N-trimethyllysine dioxygenase converts 6-N-trimethyllysine to 3-hydroxy-6-N-trimethyllysine as the first step for carnitine biosynthesis. Because the subsequent carnitine biosynthesis enzymes are cytosolic, 3-hydroxy-6-N-trimethyllysine must be transported out of the mitochondria by a putative mitochondrial 6-N-trimethyllysine/3-hydroxy-6-N-trimethyllysine transporter system. Plasma -N-trimethyllysine concentrations are significantly lower in systemic carnitine deficiency patients compared to normal individuals, but no significant difference in urinary -N-trimethyllysine excretion is seen between the two groups. D050258 - Mitosis Modulators > D008934 - Mitogens
Allysine
Allysine (CAS: 1962-83-0), also known as 2-amino-6-oxohexanoic acid or 6-oxonorleucine, belongs to the class of organic compounds known as alpha-amino acids. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Outside of the human body, allysine has been detected, but not quantified in, several different foods, such as winged beans, wasabi, common verbena, arrowhead, and oats. This could make allysine a potential biomarker for the consumption of these foods. Allysine is a derivative of lysine used in the production of elastin and collagen. It is produced by the actions of the enzyme lysyl oxidase in the extracellular matrix and is essential in the crosslink formation that stabilizes collagen and elastin.
L-Aspartate-semialdehyde
L-Aspartate-semialdehyde (CAS: 15106-57-7) is involved in both the lysine biosynthesis I and homoserine biosynthesis pathways. In the lysine biosynthesis I pathway, L-aspartate-semialdehyde is produced from a reaction between L-aspartyl-4-phosphate and NADPH, with phosphate and NADP+ as byproducts. The reaction is catalyzed by aspartate-semialdehyde dehydrogenase. L-Aspartate-semialdehyde reacts with pyruvate to produce L-2,3-dihydrodipicolinate and water. Dihydrodipicolinate synthase catalyzes this reaction. In the homoserine biosynthesis pathway, L-aspartate-semialdehyde is produced from a reaction between L-aspartyl-4-phosphate and NADPH, with phosphate and NADP+ as byproducts. The reaction is catalyzed by aspartate-semialdehyde dehydrogenase. L-Aspartate-semialdehyde reacts with NAD(P)H and H+ to form homoserine and NAD(P)+. L-Aspartate-semialdehyde is involved in both the lysine biosynthesis I and homoserine biosynthesis pathways.
Dopaquinone
Dopaquinone, also known as o-dopaquinone or L-dopaquinone, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha-amino acids which have the L-configuration of the alpha-carbon atom. Dopaquinone is slightly soluble (in water) and a moderately acidic compound (based on its pKa). L-Dopaquinone is a metabolite of L-DOPA and a precursor of melanin. Melanin is synthesized from tyrosine by hydroxylation to dihydroxyphenylalanine (DOPA) and subsequent oxidation to dopaquinone. Both reactions are catalyzed by the enzyme tyrosinase, which is the rate-limiting step. Dopaquinone has an ortho-quinone ring, which is known to be neurotoxic and highly reactive with many other compounds (PMID: 413870). Dopaquinone typically combines with cysteine to form pheomelanin (a pigment-polymer). Alternatively, dopaquinone can be converted to leucodopachrome and eventually to eumelanin (also a pigment-polymer). Dopaquinone can be found in skin and feces. Within the cell, dopaquinone is primarily located in the cytoplasm. Dopaquinone is involved in several metabolic disorders, some of which include transient tyrosinemia, hawkinsinuria, tyrosinemia type I, and alkaptonuria. Chronically high levels of dopaquinone are associated with Parkinsons disease (PD). Many Parkinsons patients are treated with L-DOPA. However, long-term treatment with L-DOPA may actually worsen symptoms or result in neurotic and psychotic symptoms. These may be due to dopachrome and dopaquinone accumulating in the brain of L-DOPA treated patients (PMID: 19131041, PMID: 12373519). Dopaquinone is a substrate of enzyme monophenol monooxygenase [EC 1.14.18.1] in tyrosine metabolism pathway (KEGG). [HMDB]
O-Phosphohomoserine
O-phosphohomoserine is a naturally occurring analogue of phosphonate amino acids. O-phosphohomoserine has been found in trace amounts in shotgun-metabolomics analysis in mouse tissue extracts, and is the substrate of a threonine analog enzyme in murine species. O-phosphohomoserine, an analogue of the excitatory amino acid antagonist 2-amino-phosphonovalerate is an N-methyl-D-aspartate (NMDA) antagonist. (PMID: 3528930, 17034760, 17665876) [HMDB] O-phosphohomoserine is a naturally occurring analogue of phosphonate amino acids. O-phosphohomoserine has been found in trace amounts in shotgun-metabolomics analysis in mouse tissue extracts, and is the substrate of a threonine analog enzyme in murine species. O-phosphohomoserine, an analogue of the excitatory amino acid antagonist 2-amino-phosphonovalerate is an N-methyl-D-aspartate (NMDA) antagonist. (PMID: 3528930, 17034760, 17665876).
L-Glutamic gamma-semialdehyde
L-glutamic-gamma-semialdehyde, also known as 5-oxo-L-norvaline or glutamic acid gamma-semialdehyde, (L)-isomer, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. L-glutamic-gamma-semialdehyde is soluble (in water) and a moderately acidic compound (based on its pKa). L-glutamic-gamma-semialdehyde can be found in a number of food items such as rubus (blackberry, raspberry), jackfruit, loganberry, and plains prickly pear, which makes L-glutamic-gamma-semialdehyde a potential biomarker for the consumption of these food products. L-glutamic-gamma-semialdehyde exists in all living species, ranging from bacteria to humans. In humans, L-glutamic-gamma-semialdehyde is involved in the arginine and proline metabolism. L-glutamic-gamma-semialdehyde is also involved in several metabolic disorders, some of which include hyperornithinemia-hyperammonemia-homocitrullinuria [hhh-syndrome], prolidase deficiency (PD), arginine: glycine amidinotransferase deficiency (AGAT deficiency), and ornithine aminotransferase deficiency (OAT deficiency). Glutamic gamma-semialdehyde is the metabolic precursor for proline biosynthesis. The conversion from L-Glutamate, an ATP- and NADPH-dependent reaction, is catalyzed by the enzyme Delta-1-pyrroline-5-carboxylate synthetase (P5CS) (OMIM 138250). L-Glutamic-gamma-semialdehyde can also be converted to or be formed from the amino acids L-ornithine (EC 2.6.1.13) and L-proline (EC 1.5.99.8 and EC 1.5.1.2). It is also one of the few metabolites that can be a precursor to other metabolites of both the urea cycle and the citric acid cycle (BioCyc).
3-Hydroxy-N6,N6,N6-trimethyl-L-lysine
3-Hydroxy-N6,N6,N6-trimethyl-L-lysine is found within the Lysine degration pathway; it is the byproduct of trimethyllysine dioxygenase (EC 1.14.11.8) which converts N6-Hydroxy-trimethyl-lysine to Glycine and 4-Trimethyl-ammoniobutanal. Because carnitine is the final product of the Lysine degration pathway, this compound is often associated with carnitine defiency disorders. (PMID: 16707092) The compound is also a byproduct of glycine hydroxymethyltransferase (EC 2.1.2.1) and Lyases (EC 4.1.2.-). [HMDB] 3-Hydroxy-N6,N6,N6-trimethyl-L-lysine is found within the Lysine degration pathway; it is the byproduct of trimethyllysine dioxygenase (EC 1.14.11.8) which converts N6-Hydroxy-trimethyl-lysine to Glycine and 4-Trimethyl-ammoniobutanal. Because carnitine is the final product of the Lysine degration pathway, this compound is often associated with carnitine defiency disorders. (PMID: 16707092) The compound is also a byproduct of glycine hydroxymethyltransferase (EC 2.1.2.1) and Lyases (EC 4.1.2.-).
L-Dopachrome
Dopachrome is a cyclization product of L-DOPA and is an intermediate in the biosynthesis of melanin. Dopaquinone has an ortho-quinone ring, which is known to be neurotoxic and highly reactive with many other compounds (PMID: 413870). Dopachrome spontaneously gives rise to 5,6-dihydroxyindole (DHI) or it can be enzymatically metabolized by dopachrome tautomerase to give 5,6-dihydroxyindole-2-carboxylic acid (DHICA). DHI and its oxidation products are also toxic to cells. Many Parkinsons patients are treated with L-DOPA. However, long-term treatment with L-DOPA may actually worsen symptoms or may result in neurotic and psychotic symptoms. These may be due to dopachrome and dopaquinone accumulating in the brain of L-DOPA treated patients (PMID: 19131041, PMID: 12373519). The non-decarboxylative tautomerization of L-dopachrome to 5,6-dihydroxyindole-2-carboxylic acid in the melanin biosynthetic pathway is catalyzed by Tyrosinase-related protein-2, a melanocyte-specific enzyme. (PMID 11095412) [HMDB]
Hydroxylated lecithin
Hydroxylated lecithin is used as a food additive [EAFUS] ("EAFUS: Everything Added to Food in the United States. [http://www.eafus.com/]") D000890 - Anti-Infective Agents > D000998 - Antiviral Agents D000970 - Antineoplastic Agents
5-phosphonooxy-L-lysine
5-phosphonooxy-l-lysine is a substrate for: Hydroxylysine kinase, and 5-phosphohydroxy-L-lysine phospho-lyase.
Selenocysteine
Selenocysteine is an amino acid that is present in several enzymes (for example glutathione peroxidases, tetraiodothyronine 5 deiodinases, thioredoxin reductases, formate dehydrogenases, glycine reductases and some hydrogenases). Selenocysteine has a structure similar to cysteine, but with an atom of selenium taking the place of the usual sulfur. Proteins that include a selenocysteine residue are called selenoproteins (Wikipedia). Selenocysteine is a naturally occurring amino acid in both eukaryotic and prokaryotic organisms. It is found in tRNAs and in the catalytic site of some enzymes. The genes for glutathione peroxidase and formate dehydrogenase contain the TGA codon, which codes for this amino acid (Pubchem). Formed by seleniferous plants, e.g. onion, cabbage
Selenohomocysteine
Selenohomocysteine is the precursor of selenocysteine, which is synthesized by catalysis of cystathionine beta-synthase (EC 4.2.1.22) and cystathionine gamma-lyase (EC 4.4.1.1), in mammalian systems (both enzymes require pyridoxal phosphate). Selenohomocysteine (lactone) has been found to be a competitive and irreversible inhibitor of lysyl oxidase; this may relate to the development of connective tissue defects seen in homocystinuria. L-Selenohomocysteine also can serve as a substituent donor in the beta-replacement reaction to yield selenocystathionine. (PMID: 10609891, 9405445, 6456763, 3338973) [HMDB]. Selenohomocysteine is found in many foods, some of which are alaska wild rhubarb, kai-lan, towel gourd, and vanilla. Selenohomocysteine (CAS: 29412-93-9) is the precursor of selenocysteine, which is synthesized by the catalysis of cystathionine beta-synthase (EC 4.2.1.22) and cystathionine gamma-lyase (EC 4.4.1.1) in mammalian systems (both enzymes require pyridoxal phosphate). Selenohomocysteine (lactone) has been found to be a competitive and irreversible inhibitor of lysyl oxidase; this may relate to the development of connective tissue defects seen in homocystinuria. L-Selenohomocysteine also can serve as a substituent donor in the beta-replacement reaction to yield selenocystathionine (PMID: 10609891, 9405445, 6456763, 3338973).
Selenocystathionine
Selenocystathionine (CAS: 2196-58-9), also known as SeCysta, belongs to the class of organic compounds known as alpha-amino acids. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Selenocystathionine is a very strong basic compound (based on its pKa). Selenocystathionine participates in a number of enzymatic reactions. In particular, selenocystathionine can be converted into selenocysteine and 2-ketobutyric acid through the action of the enzyme cystathionine gamma-lyase. Selenocystathionine is formed from selenohomocysteine by the enzyme cystathionine beta-synthase (EC 4.2.1.22) as a by-product of cystathionine synthesis. Selenocystathionine is consumed in the diet and is one of the main compounds present in plants that tend to hyperaccumulate selenium for use as an elemental plant defence mechanism (PMID: 10026151, 6456763, 16920881). Selenocystathionine is formed from Selenohomocysteine by the enzyme cystathionine beta-synthase (EC 4.2.1.22), as a by-product of cystathionine synthesis. Selenocystathionine is consumed in the diet, and is one of the main compounds present in plants that tend to hyperaccumulate selenium and use it as an elemental plant defense mechanism. (PMID: 10026151, 6456763, 16920881) [HMDB]
L-4-Hydroxyglutamate semialdehyde
L-4-Hydroxyglutamate semialdehyde is an intermediate in Arginine and proline metabolism. L-4-Hydroxyglutamate semialdehyde is the 4th to last step in the synthesis of Glyoxylate and is converted from L-erythro-4-Hydroxyglutamate via the enzyme 1-pyrroline-5-carboxylate dehydrogenase (EC 1.5.1.12). It is then converted to L-1-Pyrroline-3-hydroxy-5-carboxylate via enzymtic reaction. [HMDB] L-4-Hydroxyglutamate semialdehyde is an intermediate in Arginine and proline metabolism. L-4-Hydroxyglutamate semialdehyde is the 4th to last step in the synthesis of Glyoxylate and is converted from L-erythro-4-Hydroxyglutamate via the enzyme 1-pyrroline-5-carboxylate dehydrogenase (EC 1.5.1.12). It is then converted to L-1-Pyrroline-3-hydroxy-5-carboxylate via enzymtic reaction.
O-Phospho-4-hydroxy-L-threonine
O-Phospho-4-hydroxy-L-threonine is involved in the vitamin B6 metabolism system. O-Phospho-4-hydroxy-L-threonine is a precursor for pyridoxine. O-Phospho-4-hydroxy-L-threonine can be converted to 4-hydroxy-L-threonine and 2-Amino-3-oxo-4-phosphonooxybutyrate by threonine synthase [EC:4.2.3.1] and 4-hydroxythreonine-4-phosphate dehydrogenase [EC:1.1.1.262], respectively. [HMDB] O-Phospho-4-hydroxy-L-threonine is involved in the vitamin B6 metabolism system. O-Phospho-4-hydroxy-L-threonine is a precursor for pyridoxine. O-Phospho-4-hydroxy-L-threonine can be converted to 4-hydroxy-L-threonine and 2-Amino-3-oxo-4-phosphonooxybutyrate by threonine synthase [EC:4.2.3.1] and 4-hydroxythreonine-4-phosphate dehydrogenase [EC:1.1.1.262], respectively.
4-Acetamido-2-aminobutanoic acid
4-Acetamido-2-aminobutanoic acid is found in sugar bee
Cucumopine
Cucumopine, also known as mikimopine or cucumopine, (4r-cis)-isomer, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. Cucumopine is slightly soluble (in water) and a moderately acidic compound (based on its pKa). Cucumopine can be found in carrot and wild carrot, which makes cucumopine a potential biomarker for the consumption of these food products.
Glycine-betaxanthin
Homomethionine
Homomethionine (CAS: 6094-76-4) belongs to the class of organic compounds known as alpha-amino acids. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Homomethionine is possibly neutral. Homomethionine has been detected, but not quantified in, several different foods, such as lima beans, red huckleberries, catjang pea, Chinese chestnuts, and pepper (C. annuum). This could make homomethionine a potential biomarker for the consumption of these foods. Homomethionine is found in brassicas and is isolated from cabbage and horseradish. Isolated from cabbage and horseradish. L-2-Amino-5-(methylthio)pentanoic acid is found in many foods, some of which are pepper (c. frutescens), vanilla, cauliflower, and pineappple sage.
2-aminobutyrate
L-alpha-Aminobutyric acid, also known as (S)-2-aminobutanoic acid, homoalanine, 2-AABA, or alpha-Aminobutyric acid, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-Amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. Amino acids are organic compounds that contain amino (‚ÄìNH2) and carboxyl (‚ÄìCOOH) functional groups, along with a side chain (R group) specific to each amino acid. L-alpha-Aminobutyric acid is a non-proteogenic amino acid that can be found in the human kidney, in liver tissues, and in most biofluids or excreta (e.g. feces, breast milk, urine, and blood). Within the cell, L-alpha-aminobutyric acid is primarily located in the cytoplasm. alpha-Aminobutyric acid is biosynthesized by transamination of oxobutyrate, a metabolite in isoleucine biosynthesis. As a non-proteogenic amino acid, alpha-aminobutyric acid can be used by nonribosomal peptide synthases. One example of a nonribosomal peptide containing alpha-aminobutyric acid is ophthalmic acid, which was first isolated from calf lens. alpha-Aminobutyric acid is a non-essential amino acid that is primarily derived from the catabolism of methionine, threonine, and serine. High protein diets can result in significantly higher alpha-aminobutyrate levels in plasma (PMID: 26227325). alpha-Aminobutyric acid is elevated in the plasma of children with Reyes syndrome, tyrosinemia, homocystinuria, nonketotic hyperglycinemia, and ornithine transcarbamylase deficiency (PMID: 420125). alpha-Aminobutyric acid is one of the three isomers of aminobutyric acid. The two others are the neurotransmitter gamma-aminobutyric acid (GABA) and beta-aminobutyric acid (BABA) which is known for inducing plant disease resistance. alpha-Aminobutyric acid (AABA) is an isomer of the amino acid aminobutyric acid. It is a key intermediate in the biosynthesis of ophthalmic acid or ophthalmate. L-2-Aminobutanoic acid is found in common pea. α-Aminobutyric acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=80-60-4 (retrieved 2024-06-29) (CAS RN: 2835-81-6). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). H-Abu-OH, one of the three isomers of aminobutyric acid, is elevated in the plasma of children with with Reye's syndrome, tyrosinemia, homocystinuria, nonketotic hyperglycinemia, and ornithine transcarbamylase deficiency.
L-Allothreonine
L-allothreonine is the L-enantiomer of allothreonine. It has a role as an Escherichia coli metabolite and a Saccharomyces cerevisiae metabolite. It is an enantiomer of a D-allothreonine. It is a tautomer of a L-allothreonine zwitterion. Allothreonine is the substrate of the enzyme Serine hydroxymethyltransferase1 (SHMT, EC 2.1.2.1), a human cytoplasmic mRNA binding protein. SHMT uses pyridoxal 5-phosphate (PLP) and tetrahydropteroylglutamate (H4PteGlu) as coenzymes and catalyzes the reversible interconversion of serine and glycine. In addition to these physiological reactions, SHMT also catalyzes, in the absence of H4PteGlu, the retroaldol cleavage of several 3-hydroxyamino acids, such as allothreonine. Allothreonine is a plant metabolite that appears in the human diet in variable concentrations depending on: plant species, physiological changes during plant growth, senescence, and reactions to environmental stress or to changes due to plant transformation (PMID:10858298, 10952545). Allothreonine is the substrate of the enzyme Serine hydroxymethyltransferase1 (SHMT, EC 2.1.2.1), a human cytoplasmic mRNA binding protein. SHMT uses pyridoxal 5-phosphate (PLP) and tetrahydropteroylglutamate (H4PteGlu) as coenzymes and catalyzes the reversible interconversion of serine and glycine. In addition to these physiological reactions, SHMT also catalyzes, in the absence of H4PteGlu, the retroaldol cleavage of several 3-hydroxyamino acids, such as allothreonine. Allothreonine. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=144-98-9 (retrieved 2024-07-15) (CAS RN: 144-98-9). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). D-Allothreonine is the D type stereoisomer of Allothreonine. D-Allothreonine is a peptido-lipid derived from bacteria. D-Allothreonine, amide-linked to the D-galacturonic acid, is also a constituent in the polysaccharide[1][2]. L-Allothreonine (H-allo-Thr-OH) is an endogenous metabolite.
L-2-Amino-3-oxobutanoic acid
L-2-Amino-3-oxobutanoic acid or L-2-amino acetic acid is involved in glycine/serine metabolism and is a breakdown product from glycine. It spontaneously decomposes to aminoacetone. Delta-aminolevuliinate synthase is the enzyme that catalyzes the interconversion between glycine and L-2-amino-3-oxobutanoic acid. Glycine C-acetyltransferase is also capable of catalyzing this reaction. [HMDB] L-2-Amino-3-oxobutanoic acid or L-2-amino acetic acid is involved in glycine/serine metabolism and is a breakdown product from glycine. It spontaneously decomposes to aminoacetone. Delta-aminolevuliinate synthase is the enzyme that catalyzes the interconversion between glycine and L-2-amino-3-oxobutanoic acid. Glycine C-acetyltransferase is also capable of catalyzing this reaction.
Alliin
Alliin, also known as (S)-S-allyl-L-cysteine sulfoxide or (S)-3-(allylsulphinyl)-L-alanine, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. Alliin is soluble (in water) and a moderately acidic compound (based on its pKa). Alliin can be found in a number of food items such as red rice, mandarin orange (clementine, tangerine), ceylon cinnamon, and olive, which makes alliin a potential biomarker for the consumption of these food products. Garlic has been used since antiquity as a therapeutic remedy for certain conditions now associated with oxygen toxicity, and, when this was investigated, garlic did indeed show strong antioxidant and hydroxyl radical-scavenging properties, it is presumed owing to the alliin contained within. Alliin has also been found to affect immune responses in blood . 3-(Allylsulphinyl)-L-alanine is a L-alpha-amino acid. Alliin. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=556-27-4 (retrieved 2024-07-01) (CAS RN: 556-27-4). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). (±)-Alliin is the main active component of garlic. (±)-Alliin is a putative inhibitor of the main protease of SARS-CoV-2 (Mpro)[1]. Alliin, an orally active sulfoxide compound derived from garlic, exhibits hypoglycemic, antioxidant and anti-inflammatory activities[1][2]. Alliin, an orally active sulfoxide compound derived from garlic, exhibits hypoglycemic, antioxidant and anti-inflammatory activities[1][2].
2-Aminoheptanoate
2-Aminoheptanoate (CAS: 1115-90-8), also known as homonorleucine, is classified as a member of the alpha-amino acids. alpha-Amino acids are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). 2-Aminoheptanoate is considered to be a soluble (in water) and a moderately acidic compound. 2-Aminoheptanoate can be found in feces.
2-Amino-4-[(2-hydroxy-1-oxopropyl)amino]butanoic acid
2-Amino-4-[(2-hydroxy-1-oxopropyl)amino]butanoic acid is isolated from sugarbee
Hypusine
Hypusine is formed in eIF-5A by post-translational modification of one of the lysyl residues. There are two reactions and two enzymes involved:; Hypusine is an unusual amino acid found in all eukaryotes and in some archaea, but not in bacteria. The only known protein containing hypusine is eukaryotic translation initiation factor 5A (eIF-5A) and a similar protein found in archaebacteria. In human, two isoforms of eIF-5A have been described: eIF-5A-1 and eIF-5A-2. They are coded by two different genes. This protein is involved in protein biosynthesis and promotes the formation of the first peptide bond. The region surrounding the hypusine residue is highly conserved among the eukaryotes and is essential to the function of eIF-5A. Thus, hypusine and eIF-5A appear to be vital for the viability and proliferation of eukaryotic cells. [HMDB] Hypusine is formed in eIF-5A by post-translational modification of one of the lysyl residues. There are two reactions and two enzymes involved:; Hypusine is an unusual amino acid found in all eukaryotes and in some archaea, but not in bacteria. The only known protein containing hypusine is eukaryotic translation initiation factor 5A (eIF-5A) and a similar protein found in archaebacteria. In human, two isoforms of eIF-5A have been described: eIF-5A-1 and eIF-5A-2. They are coded by two different genes. This protein is involved in protein biosynthesis and promotes the formation of the first peptide bond. The region surrounding the hypusine residue is highly conserved among the eukaryotes and is essential to the function of eIF-5A. Thus, hypusine and eIF-5A appear to be vital for the viability and proliferation of eukaryotic cells.
Deoxypyridinoline
Deoxypyridinoline (DPD) is a breakdown product of type I fibrillar collagen, it occurs mainly in Type I collagen of bone. DPD shows a high specificity for bone, and the measurement of urinary DPD is not influenced by newly collagens and dietary intake. DPD cross-links of type 1 collagen are excreted in urine either as free or peptide-bound moieties. It is the peptide-bound cross-links that decrease by the greatest amount in response to bisphosphonate therapy. DPD is one of the most extensively characterized biochemical bone markers, but the interpretation of results is hampered by biologic and other preanalytical variability. Biochemical bone markers can provide a valuable tool in the management of metabolic bone diseases. Their most recognized application in clinical practice is for monitoring treatment for osteoporosis as an adjunct to bone mineral density measurements. Other applications that have been investigated include their use as a diagnostic tool for bone diseases other than osteoporosis and as predictive markers for bone loss and the risk of bone fracture. DPD measured in urine follow a circadian or diurnal cycle with a peak in the early morning and nadir in the late afternoon to early evening. The magnitude of the diurnal change, i.e., nadir concentration divided by peak concentration, expressed as a percentage is around 70\\% (range, 53-75\\%). (PMID: 11805003, 17229003, 16751696). Derived from collagen cross-links formed between adjacent lysine residues in type I collagen of bone and dentine. Released into serum during bone resorption
L-Homocystine
Homocystine is the oxidized form of homocysteine. Homocystine is a dipeptide consisting of two homocysteine molecules joined by a disulfide bond. Homocysteine is a sulfur-containing amino acid that arises during methionine metabolism. Homocystine occurs only transiently before being reduced to homocysteine and converted to the harmless cystathionine via a vitamin B6-dependent enzyme. Homocystine and homocysteine-cysteine mixed disulfides account for >98\\\% of total homocysteine in plasma from healthy individuals (PMID 11592966). Homocystine has been shown to stereospecifically induce endothelial nitric oxide synthase-dependent lipid peroxidation in endothelial cells, thereby inducing a vascular cell type-specific oxidative stress. This vascular stress is associated with atherothrombotic cardiovascular disease (PMID: 14980706). High levels of homocysteine (and homocysteine) can be found in individuals suffering from homocystinura due to cystathionine synthase deficiency (PMID: 4685596) Homocystine is the double-bonded form of homocysteine, but it occurs only transiently before being converted to the harmless cystathionine via a vitamin B6-dependent enzyme. L-Homocystine is the oxidized member of the L-homocysteine. Homocysteine is a pro-thrombotic factor, vasodilation impairing agent, pro-inflammatory factor and endoplasmatic reticulum-stress inducer used to study cardiovascular disease mechanisms.
L-Pipecolic acid
L-pipecolic acid is a normal human metabolite present in human blood, where is present as the primary enantiomer of pipecolic acid. L-pipecolic acid is a cyclic imino acid (contains both imino (>C=NH) and carboxyl (-C(=O)-OH) functional groups) produced during the degradation of lysine, accumulates in body fluids of infants with generalized genetic peroxisomal disorders, including Zellweger syndrome (OMIM 214100), neonatal adrenoleukodystrophy (OMIM 202370), and infantile Refsum disease (OMIM 266510). L-pipecolic acid levels are also elevated in patients with chronic liver diseases. L-pipecolic acid is the substrate of delta1-piperideine-2-carboxylate reductase (EC 1.5.1.21) in the pathway of lysine degradation (PMID: 2717271, 8305590, 1050990). Present in beans and other legumes, and in lesser quantities in other plants including barley, hops, malt and mushrooms. L-Pipecolic acid is found in many foods, some of which are macadamia nut (m. tetraphylla), linden, tinda, and cumin. L-Pipecolic acid (H-HoPro-OH) is a breakdown product of lysine, accumulates in body fluids of infants with generalized genetic peroxisomal disorders, such as Zellweger syndrome, neonatal adrenoleukodystrophy. L-Pipecolic acid (H-HoPro-OH) is a breakdown product of lysine, accumulates in body fluids of infants with generalized genetic peroxisomal disorders, such as Zellweger syndrome, neonatal adrenoleukodystrophy. Pipecolic acid, a metabolite of Lysine, is an important precursor of many useful microbial secondary metabolites. Pipecolic acid can be used as a diagnostic marker of Pyridoxine-dependent epilepsy[1][2]. Pipecolic acid, a metabolite of Lysine, is an important precursor of many useful microbial secondary metabolites. Pipecolic acid can be used as a diagnostic marker of Pyridoxine-dependent epilepsy[1][2].
Pyridinoline
Derived from collagen cross-links formed between adjacent hydroxylysine residues in type I and type II collagen of bone and cartilage respectively. Released into serum during bone resorption Pyridinoline is a breakdown product of bone collagen. It can be used as a bone marker to measure osteoclastic activity.
Cystathionine sulfoxide
One of the unusual cystathionine metabolites found in the urine of patients with cystathioninuria [HMDB] One of the unusual cystathionine metabolites found in the urine of patients with cystathioninuria.
Pentosidine
Pentosidine is a carbohydrate-derived advanced glycation end products (AGEs) that is considerably elevated in uremic patients. It has been identified as a uremic toxin according to the European Uremic Toxin Working Group (PMID: 22626821). Derived from ribose, a pentose, pentosidine forms fluorescent cross-links between the arginine and lysine residues in collagen. It is formed in a reaction of the amino acids with the Maillard reaction products of ribose. Although it is present only in trace concentrations among tissue proteins, it is useful for assessing cumulative damage to proteins-advanced glycation endproductsThis compound per se has no biological activities but is highly correlated to the levels of precursors of carbonyl compounds, and for this reason is considered a reliable surrogate marker for AGEs. The modification of proteins in uremia is not limited to AGEs, since advanced lipoxidation end products are also demonstrable in plasma proteins in uremia. The accumulation of these compounds does not seem to be dependent only on the decline of renal function. Carbonyl precursors of AGEs and advanced lipoxidation end products are markedly elevated in uremic patients. Preliminary cross-sectional studies in haemodialysis patients seem to indicate that the AGEs and carbonyl stress may be involved in the pathogenesis of alterations in left ventricular geometry and function in these patients. (PMID 11051031). The plasma pentosidine level in diabetic nephropathy was found to be determined by factors such as renal function control of glucose and the patients age; of these, renal function was the most critical factor. The pathological role of AGEs in diabetic nephropathy, is in the expanded mesangial area of diffuse diabetic glomerulosclerosis, with nodular lesions, characteristic of diabetic nephropathy. These suggests a potential link of AGEs accumulation, which may be determined by renal function, control of glucose and age, to renal tissue damage in diabetic nephropathy. (PMID 9044316). The rate of accumulation of glycoxidation products is accelerated in diabetes and age-adjusted concentrations of two advanced glycation end-products (AGE) in tissue proteins, N(6)-carboxymethyllysine and pentosidine, correlate with the severity of complication in diabetic patients. (PMID 9044306). Pentosidine is a carbohydrate-derived advanced glycation end products (AGEs) that is considerably elevated in uremic patients. Derived from ribose, a pentose, pentosidine forms fluorescent cross-links between the arginine and lysine residues in collagen. It is formed in a reaction of the amino acids with the Maillard reaction products of ribose. Although it is present only in trace concentrations among tissue proteins, it is useful for assessing cumulative damage to proteins-advanced glycation endproductsThis compound per se has no biological activities but is highly correlated to the levels of precursors of carbonyl compounds, and for this reason is considered a reliable surrogate marker for AGEs. The modification of proteins in uremia is not limited to AGEs, since advanced lipoxidation end products are also demonstrable in plasma proteins in uremia. The accumulation of these compounds does not seem to be dependent only on the decline of renal function. Carbonyl precursors of AGEs and advanced lipoxidation end products are markedly elevated in uremic patients. Preliminary cross-sectional studies in haemodialysis patients seem to indicate that the AGEs and carbonyl stress may be involved in the pathogenesis of alterations in left ventricular geometry and function in these patients. (PMID 11051031) D019995 - Laboratory Chemicals > D007202 - Indicators and Reagents > D003432 - Cross-Linking Reagents
Deoxyhypusine
Deoxyhypusine is an amino acid derivative of the unusual amino acid known as hypusine. It is a substrate of Deoxyhypusine synthase which catalyzes the cleavage of the polyamine spermidine and transfer of its 4-aminobutyl moiety to the ε-amino group of one specific lysine residue of the eIF-5A precursor to form deoxyhypusine and 1,3-diaminopropane. By the addition of a hydroxyl group to the deoxyhypusine residue deoxyhypusine hydroxylase mediates the formation of hypusine. [HMDB] Deoxyhypusine is an amino acid derivative of the unusual amino acid known as hypusine. It is a substrate of deoxyhypusine synthase which catalyzes the cleavage of the polyamine spermidine and transfer of its 4-aminobutyl moiety to the ε-amino group of one specific lysine residue of the eIF-5A precursor to form deoxyhypusine and 1,3-diaminopropane. By the addition of a hydroxyl group to the deoxyhypusine residue, deoxyhypusine hydroxylase mediates the formation of hypusine (Wikipedia).
Topaquinone
Topaquinone (TPQ), is the quinone of 2,4,5-trihydroxyphenylalanine. TPQ is the cofactor in most copper-containing amine oxidases. It is produced by post-translational modification of a strictly conserved active-site tyrosine residue with the participation of the copper ion at the active site. Once formed, TPQ acts as a switch between the heterolytic transformation of amine substrates to aldehydes, via a pyridoxal phosphate-like Schiff base complex, and one electron chemistry involving reduction of molecular oxygen (PMID: 12686122) [HMDB] Topaquinone (TPQ), is the quinone of 2,4,5-trihydroxyphenylalanine. TPQ is the cofactor in most copper-containing amine oxidases. It is produced by post-translational modification of a strictly conserved active-site tyrosine residue with the participation of the copper ion at the active site. Once formed, TPQ acts as a switch between the heterolytic transformation of amine substrates to aldehydes, via a pyridoxal phosphate-like Schiff base complex, and one electron chemistry involving reduction of molecular oxygen (PMID: 12686122).
Thioproline
Thioproline (CAS: 444-27-9), also known as 1,3-thiazolidine-4-carboxylic acid or gamma-thioproline, belongs to the class of organic compounds known as L-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom. Thioproline has been identified in the human placenta (PMID: 32033212).
Methionine sulfone
S-dioxymethionine, also known as (S)-amino-4-(methylsulphonyl)butyric acid or methionine sulfone, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. S-dioxymethionine is soluble (in water) and a moderately acidic compound (based on its pKa). S-dioxymethionine can be found in garden onion, which makes S-dioxymethionine a potential biomarker for the consumption of this food product. Methionine sulfone (CAS: 820-10-0), also known as L-methionine-S-dioxide, belongs to the class of organic compounds known as L-alpha-amino acids. These are alpha-amino acids which have the L-configuration at the alpha-carbon atom. Methionine sulfone is a very strong basic compound (based on its pKa). Methionine sulfone has been detected, but not quantified, in garden onions. This could make methionine sulfone a potential biomarker for the consumption of these foods.
Erythro-5-hydroxy-L-lysinium(1+)
Erythro-5-hydroxy-L-lysinium(1+) is also known as (2S,5R)-2,6-Diazaniumyl-5-hydroxyhexanoate or (2S,5R)-5-Hydroxy-L-lysine. Erythro-5-hydroxy-L-lysinium(1+) is considered to be slightly soluble (in water) and acidic
L-argininium(1+)
L-argininium(1+), also known as L-Arginine or DL Arginine acetate, monohydrate, is classified as a member of the L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. L-argininium(1+) is considered to be soluble (in water) and acidic
Alpha-D-mannosyl-beta-D-mannosyldiacetylchitobiosyldiphosphodolichol
Alpha-D-mannosyl-beta-D-mannosyldiacetylchitobiosyldiphosphodolichol is classified as a member of the Polyprenyl phospho carbohydrates. Polyprenyl phospho carbohydrates are polyprenyl phosphates with a carbohydrate moiety attached to it. Alpha-D-mannosyl-beta-D-mannosyldiacetylchitobiosyldiphosphodolichol is considered to be practically insoluble (in water) and acidic
N6-Carboxymethyllysine
N6-Carboxymethyllysine (CML), also known as epsilon-(carboxymethyl)lysine, belongs to the class of organic compounds known as L-alpha-amino acids. These are alpha-amino acids which have the L-configuration of the alpha-carbon atom. CML is a Maillard reaction product, or dietary advanced glycation end-products (d-AGE), formed as a result of the thermal treatment of foods. Due to its chemical stability and its ubiquity in foods and in vivo, CML is used as a biomarker for the ingestion of thermally treated foods. CML is metabolized by intestinal bacteria under anaerobic conditions (PMID: 31091091).
S-(2-Oxo-2-carboxyethyl)homocysteine
S-(2-Oxo-2-carboxyethyl)homocysteine, abbreviated as OCEHC, is a cystathionine mono-oxo acid metabolite found in the urine of a cystathioninuria patient (PMID: 8373176).
N5-Acetylornithine
N5-Acetylornithine, also known as N(delta)-acetylornithine, belongs to the class of organic compounds known as N-acyl-L-alpha-amino acids. These are N-acylated alpha-amino acids which have the L-configuration of the alpha-carbon atom. N5-Acetylornithine has been identified in the human placenta (PMID: 32033212).
N2-Methyl-L-lysine
N2-Methyl-L-lysine, also known as N(a)-methyl-L-lysine, belongs to the class of organic compounds known as l-alpha-amino acids. Lysine methylation displays the highest degree of complexity among known covalent histone modifications, with each site of methylation regulating the association of different effector molecules. The versatility of lysine methylation marks is perhaps best exemplified by modifications implicated in transcriptional regulation as well as being required for double-strand break repair in several organisms. Identification of the numerous biological functions encoded by histone lysine methylation is a major area of research interest. (PMID: 32119527)
N-[[(2S,3S,4R,5R)-5-[2-Chloro-6-[(3-iodophenyl)methylamino]purin-9-yl]-3,4-dihydroxyoxolan-2-yl]-hydroxymethyl]-N-methylformamide
2-(2-Chlorophenyl)-2-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)propanedioic acid
L-Lysine hydrochloride
Dietary supplement, nutrient L-lysine hydrochloride is an essential amino acid for humans with various benefits including treating herpes, increasing calcium absorption, reducing diabetes-related illnesses and improving gut health. L-lysine hydrochloride is an essential amino acid for humans with various benefits including treating herpes, increasing calcium absorption, reducing diabetes-related illnesses and improving gut health.
(+)-gamma-Hydroxy-L-homoarginine
(+)-gamma-hydroxy-l-homoarginine is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom (+)-gamma-hydroxy-l-homoarginine is soluble (in water) and a moderately acidic compound (based on its pKa). (+)-gamma-hydroxy-l-homoarginine can be found in common pea and lentils, which makes (+)-gamma-hydroxy-l-homoarginine a potential biomarker for the consumption of these food products.
S-Butylcysteine sulfoxide
S-butylcysteine sulfoxide is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. S-butylcysteine sulfoxide is soluble (in water) and a moderately acidic compound (based on its pKa). S-butylcysteine sulfoxide can be found in soft-necked garlic, which makes S-butylcysteine sulfoxide a potential biomarker for the consumption of this food product.
S-Propylcysteine sulphoxide
S-propylcysteine sulphoxide, also known as pcso, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. S-propylcysteine sulphoxide is soluble (in water) and a moderately acidic compound (based on its pKa). S-propylcysteine sulphoxide can be found in soft-necked garlic, which makes S-propylcysteine sulphoxide a potential biomarker for the consumption of this food product.
Arginine hydrochloride
Dietary supplement, nutrient. Arginine (abbreviated as Arg or R) is an alpha-amino acid. The L-form is one of the 20 most common natural amino acids. B - Blood and blood forming organs > B05 - Blood substitutes and perfusion solutions > B05X - I.v. solution additives > B05XB - Amino acids Dietary supplement, nutrient L-Arginine hydrochloride ((S)-(+)-Arginine hydrochloride) is the nitrogen donor for synthesis of nitric oxide, a potent vasodilator that is deficient during times of sickle cell crisis. L-Arginine hydrochloride ((S)-(+)-Arginine hydrochloride) is the nitrogen donor for synthesis of nitric oxide, a potent vasodilator that is deficient during times of sickle cell crisis.
L-Cysteic acid
Cysteinesulfonic acid, also known as (2r)-2-amino-3-sulfopropanoic acid or 3-sulfoalanine, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. Cysteinesulfonic acid is soluble (in water) and an extremely strong acidic compound (based on its pKa). Cysteinesulfonic acid can be found in a number of food items such as roman camomile, pili nut, chicory, and garden tomato, which makes cysteinesulfonic acid a potential biomarker for the consumption of these food products.
4,5-seco-dopa
4,5-seco-dopa is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. 4,5-seco-dopa is practically insoluble (in water) and a moderately acidic compound (based on its pKa). 4,5-seco-dopa can be found in a number of food items such as safflower, yautia, pitanga, and anise, which makes 4,5-seco-dopa a potential biomarker for the consumption of these food products.
N5-formyl-N5-hydroxy-L-ornithine
N5-formyl-n5-hydroxy-l-ornithine is a member of the class of compounds known as L-alpha-amino acids. L-alpha-amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. N5-formyl-n5-hydroxy-l-ornithine is soluble (in water) and a moderately acidic compound (based on its pKa). N5-formyl-n5-hydroxy-l-ornithine can be found in a number of food items such as chinese chives, european chestnut, okra, and mung bean, which makes n5-formyl-n5-hydroxy-l-ornithine a potential biomarker for the consumption of these food products.
Asparagine-betaxanthin
glutamine-betaxanthin
D004396 - Coloring Agents > D050858 - Betalains