Valine

Valine (abbreviated as Val or V) is an -amino acid with the chemical formula HO2CCH(NH2)CH(CH3)2. It is named after the plant valerian. L-Valine is one of 20 proteinogenic amino acids. Its codons are GUU, GUC, GUA, and GUG. This essential amino acid is classified as nonpolar. Along with leucine and isoleucine, valine is a branched-chain amino acid. Branched chain amino acids (BCAA) are essential amino acids whose carbon structure is marked by a branch point. These three amino acids are critical to human life and are particularly involved in stress, energy and muscle metabolism. BCAA supplementation as therapy, both oral and intravenous, in human health and disease holds great promise. "BCAA" denotes valine, isoleucine and leucine which are branched chain essential amino acids. Despite their structural similarities, the branched amino acids have different metabolic routes, with valine going solely to carbohydrates, leucine solely to fats and isoleucine to both. The different metabolism accounts for different requirements for these essential amino acids in humans: 12 mg/kg, 14 mg/kg and 16 mg/kg of valine, leucine and isoleucine respectively. Furthermore, these amino acids have different deficiency symptoms. Valine deficiency is marked by neurological defects in the brain, while isoleucine deficiency is marked by muscle tremors. Many types of inborn errors of BCAA metabolism exist, and are marked by various abnormalities. The most common form is the maple syrup urine disease, marked by a characteristic urinary odor. Other abnormalities are associated with a wide range of symptoms, such as mental retardation, ataxia, hypoglycemia, spinal muscle atrophy, rash, vomiting and excessive muscle movement. Most forms of BCAA metabolism errors are corrected by dietary restriction of BCAA and at least one form is correctable by supplementation with 10 mg of biotin daily. BCAA are decreased in patients with liver disease, such as hepatitis, hepatic coma, cirrhosis, extrahepatic biliary atresia or portacaval shunt; aromatic amino acids (AAA)tyrosine, tryptophan and phenylalanine, as well as methionineare increased in these conditions. Valine in particular, has been established as a useful supplemental therapy to the ailing liver. All the BCAA probably compete with AAA for absorption into the brain. Supplemental BCAA with vitamin B6 and zinc help normalize the BCAA:AAA ratio. (http://www.dcnutrition.com). In sickle-cell disease, valine substitutes for the hydrophilic amino acid glutamic acid in hemoglobin. Because valine is hydrophobic, the hemoglobin does not fold correctly. Valine is an essential amino acid, hence it must be ingested, usually as a component of proteins.

(2s)-2-amino-3-methylbutanoate
(2s)-2-amino-3-methylbutanoic acid
(s)-2-amino-3-methylbutanoate
(s)-2-amino-3-methylbutanoic acid
(s)-2-amino-3-methylbutyrate
(s)-2-amino-3-methylbutyric acid
(s)-2-amino-3-methyl-butanoate
(s)-2-amino-3-methyl-butanoic acid
(s)-valine
(s)-a-amino-b-methylbutyrate
(s)-a-amino-b-methylbutyric acid
(s)-alpha-amino-beta-methylbutyrate
(s)-alpha-amino-beta-methylbutyric acid
2-amino-3-methylbutanoate
2-amino-3-methylbutanoic acid
2-amino-3-methylbutyrate
2-amino-3-methylbutyric acid
L-(+)-a-aminoisovalerate
L-(+)-a-aminoisovaleric acid
L-(+)-alpha-aminoisovalerate
L-(+)-alpha-aminoisovaleric acid
L-valine
L-a-amino-b-methylbutyrate
L-a-amino-b-methylbutyric acid
L-alpha-amino-beta-methylbutyrate
L-alpha-amino-beta-methylbutyric acid
Valine
L-valin
V
Val


alpha-Ketoisovalerate

alpha-Ketoisovaleric acid is an abnormal metabolite that arises from the incomplete breakdown of branched-chain amino acids. alpha-Ketoisovaleric acid is a neurotoxin, an acidogen, and a metabotoxin. A neurotoxin causes damage to nerve cells and nerve tissues. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of alpha-ketoisovaleric acid are associated with maple syrup urine disease. MSUD is a metabolic disorder caused by a deficiency of the branched-chain alpha-keto acid dehydrogenase complex (BCKDC), leading to a buildup of the branched-chain amino acids (leucine, isoleucine, and valine) and their toxic by-products (ketoacids) in the blood and urine. The symptoms of MSUD often show in infancy and lead to severe brain damage if untreated. MSUD may also present later depending on the severity of the disease. If left untreated in older individuals, during times of metabolic crisis, symptoms of the condition include uncharacteristically inappropriate, extreme, or erratic behaviour and moods, hallucinations, anorexia, weight loss, anemia, diarrhea, vomiting, dehydration, lethargy, oscillating hypertonia and hypotonia, ataxia, seizures, hypoglycemia, ketoacidosis, opisthotonus, pancreatitis, rapid neurological decline, and coma.  In maple syrup urine disease, the brain concentration of branched-chain ketoacids can increase 10- to 20-fold. This leads to a depletion of glutamate and a consequent reduction in the concentration of brain glutamine, aspartate, alanine, and other amino acids. The result is a compromise of energy metabolism because of a failure of the malate-aspartate shuttle and a diminished rate of protein synthesis (PMID: 15930465). alpha-Ketoisovaleric acid is a keto-acid, which is a subclass of organic acids. 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, liver, and kidney abnormalities, seizures, coma, and possibly death. These are also the characteristic symptoms of untreated MSUD. Many affected children with organic acidemias experience intellectual disability or delayed development.

2-keto-3-methylbutyrate
2-keto-3-methylbutyric acid
2-ketoisovalerate
2-ketoisovaleric acid
2-ketoisvaleric acid
2-oxo-3-methyl-butyrate
2-oxo-3-methylbutanoate
2-oxo-3-methylbutanoic acid
2-oxo-3-methylbutyrate
2-oxo-3-methylbutyric acid
2-oxoisovalerate
2-oxoisovaleric acid
3-methyl-2-oxo-butanoate
3-methyl-2-oxo-butanoic acid
3-methyl-2-oxo-butyrate
3-methyl-2-oxo-butyric acid
3-methyl-2-oxobutanoate
3-methyl-2-oxobutanoic acid
3-methyl-2-oxobutinoate
3-methyl-2-oxobutinoic acid
3-methyl-2-oxobutyrate
3-methyl-2-oxobutyric acid
Dimethylpyruvate
Dimethylpyruvic acid
Isopropylglyoxylate
Isopropylglyoxylic acid
Ketovaline
A-keto-isovalerate
A-keto-isovaleric acid
A-keto-b-methylbutyrate
A-keto-b-methylbutyric acid
A-ketoisovalerate
A-ketoisovaleric acid
A-oxo-b-methylbutyrate
A-oxo-b-methylbutyric acid
A-oxoisovalerate
A-oxoisovaleric acid
Alpha-keto-isovalerate
Alpha-keto-isovaleric acid
Alpha-keto-beta-methylbutyrate
Alpha-keto-beta-methylbutyric acid
Alpha-ketoisovalerate
Alpha-ketoisovaleric acid
Alpha-oxo-beta-methylbutyrate
Alpha-oxo-beta-methylbutyric acid
Alpha-oxoisovalerate
Alpha-oxoisovaleric acid
2-ketovaline
Alpha-ketovaline
Alpha-oxo-beta-methylbutyricacid
α-keto-isovalerate
α-keto-isovaleric acid
A-ketovaline
α-ketovaline
A-oxo-b-methylbutyricacid
α-oxo-β-methylbutyricacid
α-oxoisovalerate
α-oxoisovaleric acid


2-Methyl-1-hydroxypropyl-ThPP is an intermediate in valine, leucine and isoleucine degradation(KEGG ID C15976). It is the second to last step in the synthesis of isobutyryl-CoA and is converted from 3-methyl-2-oxobutanoate via the enzyme 2-oxoisovalerate dehydrogenase [EC:1.2.4.4]. It is then converted to S-(2-methylpropanoyl)-dihydrolipoamide-E via the enzyme 2-oxoisovalerate dehydrogenase [EC:1.2.4.4]].


S-(2-Methylpropionyl)-dihydrolipoamide-E is an intermediate in valine, leucine and isoleucine degradation(KEGG ID C15977). It is the second to last step in the synthesis of branched chain fatty acid and is converted from 2-methyl-1-hydroxypropyl-ThPP via the enzyme 2-oxoisovalerate dehydrogenase [EC:1.2.4.4]. It is then converted to isobutyryl-CoA via the enzyme dihydrolipoyllysine-residue (2-methylpropanoyl)transferase [EC:2.3.1.168].


methacrylyl-CoA

Methacrylyl-CoA is a metabolite in the valine, leucine and isoleucine degradation pathway and highly reacts with free thiol compounds (PMID 14684172; KEGG). Cirrhosis results in a significant decrease in 3--hydroxyisobutyryl-CoA hydrolase activity, a key enzyme in the valine catabolic pathway that plays an important role in the catabolism of a potentially toxic compound, methacrylyl-CoA, formed as an intermediate in the catabolism of valine and isobutyrate. (PMID: 8938168).

2-methylprop-2-enoyl-coa
2-methylprop-2-enoyl-coenzyme a
Methacrylyl coa
Methacrylyl coenzyme a
Methacrylyl-coenzyme a
Methylacrylyl-coa
Methylacrylyl-coenzyme a
S-(2-methyl-2-propenoate
S-(2-methyl-2-propenoate) coa
S-(2-methyl-2-propenoate) coenzyme a
S-(2-methyl-2-propenoic acid


(S)-3-Hydroxyisobutyryl-CoA is s metabolite of 3-hydroxyisobutyryl-CoA hydrolase (EC 3.1.2.4 ) during beta-alanine metabolism (KEGG 00410), propanoate metabolism (KEGG 00640), and valine, leucine and isoleucine degradation (KEGG 00280). Deficiencies of this enzyme in valine degradation can result in hypotonia, poor feeding, motor delay, and subsequent neurological regression in infancy, episodes of ketoacidosis and Leigh-like changes in the basal ganglia on a magnetic resonance imaging scan (PMID 17160907).


(S)-3-hydroxyisobutyric acid

(S)-3-Hydroxyisobutyric (3-HIBA) acid is an organic acid. 3-HIBA is an intermediate in L-valine metabolism. 3-HIBA plays an important role in the diagnosis of the very rare inherited metabolic diseases 3-hydroxyisobutyric aciduria (OMIM 236795) and methylmalonic semialdehyde dehydrogenase deficiency (OMIM 603178). Patients with 3-hydroxyisobutyric aciduria excrete a significant amount of 3-HIBA not only during the acute stage but also when stable. 3-hydroxyisobutyric aciduria is caused by a 3-hydroxyisobutyryl-CoA dehydrogenase deficiency (PMID: 18329219). The severity of this disease varies from case to case. Most patients exhibit dysmorphic features, such as a small triangular face, a long philtrum, low set ears and micrognathia (PMID: 113770040, 10686279). Lactic acidemia is also found in the affected patients, indicating that mitochondrial dysfunction is involved. 3-hydroxyisobutyrate appears to specifically inhibit the function of the respiratory chain complex I-III and mitochondrial creatine kinase (PMID: 18329219).


(S)-methylmalonaldehydic acid

Methylmalonic semialdehyde is a metabolite in valine catabolism, inositol metabolism and propanoate metabolism. Methylmalonate-semialdehyde dehydrogenase (MMSDH) catalyses the NAD+ and coenzyme A-dependent conversion of methylmalonate semialdehyde to propionyl-CoA in the distal region of the L-valine catabolic pathway. MMSDH is located within the mitochondria; direct enzymatic assay of MMSDH is difficult since the substrate, methylmalonate semialdehyde, is both commercially unavailable and notoriously unstable as a b-keto acid. (PMID: 10947204).

(2s)-2-methyl-3-oxopropanoate
(2s)-2-methyl-3-oxopropanoic acid
(s)-methylmalonate semialdehyde
(s)-methylmalonic acid semialdehyde


Methylmalonate

Methylmalonic acid is a malonic acid derivative, which is a vital intermediate in the metabolism of fat and protein. In particular, the coenzyme A-linked form of methylmalonic acid, methylmalonyl-CoA, is converted into succinyl-CoA by methylmalonyl-CoA mutase in a reaction that requires vitamin B12 as a cofactor. In this way, methylmalonic acid enters the Krebs cycle and is thus part of one of the anaplerotic reactions. Abnormalities in methylmalonic acid metabolism lead to methylmalonic aciduria. This inborn error of metabolism is attributed to a block in the enzymatic conversion of methylmalonyl CoA to succinyl CoA. Methylmalonic acid is also found to be associated with other inborn errors of metabolism, including cobalamin deficiency, cobalamin malabsorption, malonyl-CoA decarboxylase deficiency, and transcobalamin II deficiency. When present in sufficiently high levels, methylmalonic acid can act as an acidogen and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of methylmalonic acid are associated with at least 5 inborn errors of metabolism, including Malonyl CoA decarboxylase deficiency, Malonic Aciduria, Methylmalonate Semialdehyde Dehydrogenase Deficiency, Methylmalonic Aciduria and Methylmalonic Aciduria Due to Cobalamin-Related Disorders. Methylmalonic 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.

1,1-ethanedicarboxylate
1,1-ethanedicarboxylic acid
2-methylmalonate
2-methylmalonic acid
Isosuccinate
Isosuccinic acid
Methyl-malonate
Methyl-malonic acid
Methyl-propanedioate
Methyl-propanedioic acid
Methylmalonate
Methylmalonic acid
Methylpropanedioate
Methylpropanedioic acid
Alpha-methylmalonic acid
2-methylpropanedioate
A-methylmalonate
A-methylmalonic acid
Alpha-methylmalonate
α-methylmalonate
α-methylmalonic acid


Isoleucine

Branched chain amino acids (BCAA) are essential amino acids whose carbon structure is marked by a branch point. These three amino acids are critical to human life and are particularly involved in stress, energy and muscle metabolism. BCAA supplementation as therapy, both oral and intravenous, in human health and disease holds great promise. "BCAA" denotes valine, isoleucine and leucine which are branched chain essential amino acids. Despite their structural similarities, the branched amino acids have different metabolic routes, with valine going solely to carbohydrates, leucine solely to fats and isoleucine to both. The different metabolism accounts for different requirements for these essential amino acids in humans: 12 mg/kg, 14 mg/kg and 16 mg/kg of valine, leucine and isoleucine respectively. Furthermore, these amino acids have different deficiency symptoms. Valine deficiency is marked by neurological defects in the brain, while isoleucine deficiency is marked by muscle tremors. BCAA are decreased in patients with liver disease, such as hepatitis, hepatic coma, cirrhosis, extrahepatic biliary atresia or portacaval shunt; aromatic amino acids (AAA)-tyrosine, tryptophan and phenylalanine, as well as methionine-are increased in these conditions. Valine, in particular, has been established as a useful supplemental therapy to the ailing liver. All the BCAA probably compete with AAA for absorption into the brain. Supplemental BCAA with vitamin B6 and zinc help normalize the BCAA:AAA ratio. The BCAA are not without side effects. Leucine alone, for example, exacerbates pellagra and can cause psychosis in pellagra patients by increasing excretion of niacin in the urine. Leucine may lower brain serotonin and dopamine. A dose of 3 g of isoleucine added to the niacin regime has cleared leucine-aggravated psychosis in schizophrenic patients. Isoleucine may have potential as an antipsychotic treatment. Leucine is more highly concentrated in foods than other amino acids. A cup of milk contains 800 mg of leucine and only 500 mg of isoleucine and valine. A cup of wheat germ has about 1.6 g of leucine and 1 g of isoleucine and valine. The ratio evens out in eggs and cheese. One egg and an ounce of most cheeses each contain about 400 mg of leucine and 400 mg of valine and isoleucine. The ratio of leucine to other BCAA is greatest in pork, where leucine is 7 to 8 g and the other BCAA together are only 3 to 4 g. (http://www.dcnutrition.com).


alpha-Keto-beta-methylvaleric acid

3-Methyl-2-oxovaleric acid is an abnormal metabolite that arises from the incomplete breakdown of branched-chain amino acids. 3-Methyl-2-oxovaleric acid is a neurotoxin, an acidogen, and a metabotoxin. A neurotoxin causes damage to nerve cells and nerve tissues. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of 3-methyl-2-oxovaleric acid are associated with maple syrup urine disease. MSUD is a metabolic disorder caused by a deficiency of the branched-chain alpha-keto acid dehydrogenase complex (BCKDC), leading to a buildup of the branched-chain amino acids (leucine, isoleucine, and valine) and their toxic by-products (ketoacids) in the blood and urine. The symptoms of MSUD often show in infancy and lead to severe brain damage if untreated. MSUD may also present later depending on the severity of the disease. If left untreated in older individuals, during times of metabolic crisis, symptoms of the condition include uncharacteristically inappropriate, extreme, or erratic behaviour and moods, hallucinations, anorexia, weight loss, anemia, diarrhea, vomiting, dehydration, lethargy, oscillating hypertonia and hypotonia, ataxia, seizures, hypoglycemia, ketoacidosis, opisthotonus, pancreatitis, rapid neurological decline, and coma.  In maple syrup urine disease, the brain concentration of branched-chain ketoacids can increase 10- to 20-fold. This leads to a depletion of glutamate and a consequent reduction in the concentration of brain glutamine, aspartate, alanine, and other amino acids. The result is a compromise of energy metabolism because of a failure of the malate-aspartate shuttle and a diminished rate of protein synthesis (PMID: 15930465). 3-Methyl-2-oxovaleric acid is a keto-acid, which is a subclass of organic acids. 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, liver, and kidney abnormalities, seizures, coma, and possibly death. These are also the characteristic symptoms of untreated MSUD. Many affected children with organic acidemias experience intellectual disability or delayed development.

(3r)-3-methyl-2-oxopentanoate
(3r)-3-methyl-2-oxopentanoic acid
(r)-3-methyl-2-oxopentanoate
(r)-3-methyl-2-oxopentanoic acid
(s)-3-methyl-2-oxopentanoate
(s)-3-methyl-2-oxopentanoic acid
2-keto-3-methylvalerate
2-keto-3-methylvaleric acid
2-oxo-3-methyl-n-valerate
2-oxo-3-methyl-n-valeric acid
2-oxo-3-methylpentanoate
2-oxo-3-methylpentanoic acid
2-oxo-3-methylvalerate
2-oxo-3-methylvaleric acid
2-oxoisoleucine
2-oxokolavenate
2-oxokolavenic acid
3-methyl-2-oxo-valerate
3-methyl-2-oxo-valeric acid
3-methyl-2-oxo-pentanoate
3-methyl-2-oxo-pentanoic acid
3-methyl-2-oxopentanoate
3-methyl-2-oxopentanoic acid
3-methyl-2-oxovalerate
3-methyl-2-oxovaleric
A-keto-b-methyl-n-valerate
A-keto-b-methyl-n-valeric acid
A-keto-b-methylvalerate
A-keto-b-methylvaleric acid
A-oxo-b-methyl-n-valerate
A-oxo-b-methyl-n-valeric acid
A-oxo-b-methylvalerate
A-oxo-b-methylvaleric acid
Alpha-keto-beta-methyl-n-valerate
Alpha-keto-beta-methyl-n-valeric acid
Alpha-keto-beta-methylvalerate
Alpha-keto-beta-methylvaleric acid
Alpha-oxo-beta-methyl-n-valerate
Alpha-oxo-beta-methyl-n-valeric acid
Alpha-oxo-beta-methylvalerate
Alpha-oxo-beta-methylvaleric acid
3-ethyl-3-methylpyruvic acid
3-ethyl-3-methylpyruvate
α-keto-β-methyl-n-valerate
α-keto-β-methyl-n-valeric acid
α-keto-β-methylvalerate
α-keto-β-methylvaleric acid
α-oxo-β-methyl-n-valerate
α-oxo-β-methyl-n-valeric acid
α-oxo-β-methylvalerate
α-oxo-β-methylvaleric acid


S-(2-Methylbutanoyl)-dihydrolipoamide-E is an intermediate in isoleucine degradation. S-(2-Methylbutanoyl)-dihydrolipoamide is normally conjugated to a lysine residue of the methylpropanoyltransferase enzyme (E stands for enzyme). The structure shown here is the free form. Specifically S-(2-Methylbutanoyl)-dihydrolipoamide-E is the 2-methylbutanoyl thioester of the reduced lipoyllysine residue in dihydrolipoyllysine-residue (2-methylpropanoyl)transferase.


2-Methylbutyryl-CoA is a a product of isoleucine catabolism. It is converted to Tiglyl-CoA by short/branched-chain acyl-CoA dehydrogenase. 2-Methylbutyryl-CoA dehydrogenase deficiency, also called 2-Methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency or MBHD, is an inherited disorder in which the body is unable to process the amino acid isoleucine properly. It is caused by a mutation in the HADH2 gene. Untreated MBHD can lead to progressive loss of motor skills, to mental retardation and to epilepsy. 2-Methylbutyryl-CoA is a substrate for Acyl-CoA dehydrogenase (short-chain specific, mitochondrial), Acyl-CoA dehydrogenase (medium-chain specific, mitochondrial) and Acyl-CoA dehydrogenase (long-chain specific, mitochondrial).


Tiglyl-CoA

Tiglyl-CoA is a metabolite in the degradation of isoleucine to propionic acid pathway. A defect in the conversion of tiglyl-CoA to alpha-methyl-beta-hydroxybutyryl-CoA, results in episodic abdominal pain and acidosis in patients with Tiglic acidemia (OMIM 275190).

(e)-2-methylcrotonoyl-coa
(e)-2-methylcrotonoyl-coenzyme a
2-methylbut-2-enoyl-coa
2-methylbut-2-enoyl-coenzyme a
2-methylcrotanoyl-coa
2-methylcrotanoyl-coenzyme a
2-methylcrotonoyl-coa
2-methylcrotonoyl-coenzyme a
2-methylcrotonyl-coa
2-methylcrotonyl-coenzyme a
Methylcrotonoyl-coa
Methylcrotonoyl-coenzyme a
Methylcrotonyl-coa
Methylcrotonyl-coenzyme a
Tigloyl-coa
Tigloyl-coenzyme a
Tiglyl-coa
Tiglyl-coenzyme a
Trans-2-methylbut-2-enoyl-coa
Trans-2-methylbut-2-enoyl-coenzyme a


2-Methyl-3-hydroxybutyryl-CoA is a substrate for 3-hydroxyacyl-CoA dehydrogenase type II, Enoyl-CoA hydratase (mitochondrial), Trifunctional enzyme alpha subunit (mitochondrial), Short chain 3-hydroxyacyl-CoA dehydrogenase (mitochondrial) and Peroxisomal bifunctional enzyme.


2-Methylacetoacetyl-CoA is a substrate for 3-hydroxyacyl-CoA dehydrogenase type II, 3-ketoacyl-CoA thiolase (mitochondrial), Peroxisomal bifunctional enzyme, Trifunctional enzyme beta subunit (mitochondrial), Short chain 3-hydroxyacyl-CoA dehydrogenase (mitochondrial) and 3-ketoacyl-CoA thiolase (peroxisomal).

2-methyl-3-acetoacetyl-coa
2-methyl-3-acetoacetyl-coenzyme a
2-methylacetoacetyl-coa
2-methylacetoacetyl-coenzyme a
S-(2-methyl-3-oxobutanoate
S-(2-methyl-3-oxobutanoate) coa
S-(2-methyl-3-oxobutanoate) coenzyme a
S-(2-methyl-3-oxobutanoic acid
Alpha-methylacetoacetyl-coa
Alpha-methylacetoacetyl-coenzyme a


Pyridoxal

Pyridoxal, also known as pyridoxaldehyde, belongs to the class of organic compounds known as pyridoxals and derivatives. Pyridoxals and derivatives are compounds containing a pyridoxal moiety, which consists of a pyridine ring substituted at positions 2,3,4, and 5 by a methyl group, a hydroxyl group, a carbaldehyde group, and a hydroxymethyl group, respectively. Pyridoxal exists as a solid, soluble (in water), and a very weakly acidic compound (based on its pKa). Pyridoxal has been found in human kidney and placenta tissues, and has also been primarily detected in blood. Within the cell, pyridoxal is primarily located in the cytoplasm. Pyridoxal exists in all living organisms, ranging from bacteria to humans. Pyridoxal can be converted into pyridoxal 5'-phosphate; which is catalyzed by the enzyme pyridoxal kinase. In humans, pyridoxal is involved in the vitamin B6 metabolism pathway and the valine, leucine and isoleucine degradation pathway. Pyridoxal is also involved in several metabolic disorders, some of which include Beta-ketothiolase deficiency, the 3-methylglutaconic aciduria type IV pathway, the methylmalonic aciduria pathway, and isobutyryl-CoA dehydrogenase deficiency. The 4-carboxyaldehyde form of vitamin B6 which is converted to pyridoxal phosphate which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid.


3-Hydroxyisovaleryl-CoA belongs to the class of organic compounds known as (s)-3-hydroxyacyl coas. These are organic compounds containing a (S)-3-hydroxyl acylated coenzyme A derivative. 3-Hydroxyisovaleryl-CoA is slightly soluble (in water) and an extremely strong acidic compound (based on its pKa). 3-Hydroxyisovaleryl-CoA has been primarily detected in urine. Within the cell, 3-hydroxyisovaleryl-CoA is primarily located in the cytoplasm. 3-Hydroxyisovaleryl-CoA exists in all living organisms, ranging from bacteria to humans. In humans, 3-hydroxyisovaleryl-CoA is involved in the valine, leucine and isoleucine degradation pathway. 3-Hydroxyisovaleryl-CoA is also involved in several metabolic disorders, some of which include the 3-methylglutaconic aciduria type III pathway, the isovaleric acidemia pathway, 3-hydroxy-3-methylglutaryl-CoA lyase deficiency, and 2-methyl-3-hydroxybutryl CoA dehydrogenase deficiency. 3-Hydroxyisovaleryl-CoA is an end product of leucine degradation. It is converted from 3-methylbut-2-enoyl-CoA by the enzyme enoyl-CoA hydratase.


BAIBA, (S)-

beta-Aminoisobutyric acid is a non-protein amino acid originating from the catabolism of thymine and valine. The concentration of beta-aminoisobutyric acid is normally low in urine as beta-aminoisobutyric acid is further catabolized by beta-aminoisobutyrate aminotransferases to methylmalonic acid semialdehyde and propionyl-CoA. beta-Aminoisobutyric acid occurs in two isomeric forms and both enantiomers of beta-aminoisobutyric acid can be detected in human urine and plasma. In plasma, the S-enantiomer is the predominant type due to active renal reabsorption. In contrast, urine almost exclusively contains the R-enantiomer of beta-aminoisobutyric acid, which is eliminated both by filtration and tubular secretion. Persistently increased levels of beta-aminoisobutyric acid have been observed in individuals with a deficiency of R (-)-beta-aminoisobutyrate-pyruvate aminotransferase. In addition, transient high levels of beta-aminoisobutyric acid have been observed under a variety of pathological conditions such as lead poisoning, starvation, in total body irradiation, and in a number of malignancies. The S-enantiomer of beta-aminoisobutyric acid is predominantly derived from the catabolism of valine. It has been suggested that altered homeostasis of beta-alanine underlies some of the clinical abnormalities encountered in patients with a dihydropyrimidine dehydrogenase (DPD) deficiency. DPD constitutes the first step of the pyrimidine degradation pathway, in which the pyrimidine bases uracil and thymine are catabolized to beta-alanine and the R-enantiomer of beta-aminoisobutyric acid respectively. In normal individuals with an intact pyrimidine degradation pathway, R-methylmalonic acid semialdehyde can be synthesized directly from the catabolism of thymine. Hence, there might be less cross-over between the valine and thymine pathway, allowing the conversion of S-methylmalonic acid semialdehyde into S-beta-aminoisobutyric acid and the subsequent accumulation of S-beta-aminoisobutyric acid in plasma (PMID: 14705962, 14292857, 14453202).

(+)-a-methyl-b-alanine
(+)-alpha-methyl-beta-alanine
(+)-b-aminoisobutyric acid
(+)-beta-aminoisobutyric acid
(s)-3-amino-2-methylpropanoate
(s)-3-amino-2-methylpropanoic acid
(s)-3-amino-isobutanoate
(s)-3-amino-isobutanoic acid
(s)-3-amino-isobutyrate
(s)-3-amino-isobutyric acid
(s)-3-amino-2-methyl-propanoate
(s)-3-amino-2-methyl-propanoic acid
(s)-b-aminoisobutyric acid
(s)-beta-aminoisobutyric acid
L-2-methyl-b-alanine
L-2-methyl-beta-alanine
L-3-amino-2-methylpropanoate
L-3-amino-2-methylpropanoic acid
L-3-amino-2-methylpropionic acid
L-3-amino-isobutanoate
L-3-amino-isobutanoic acid
L-3-amino-isobutyrate
L-3-amino-isobutyric acid
L-b-aminoisobutyrate
L-b-aminoisobutyric acid
L-beta-aminoisobutyrate
L-beta-aminoisobutyric acid
S-b-aminoisobutyrate
S-beta-aminoisobutyrate
S-beta-aminoisobutyric acid
(s)-3-aminoisobutyrate
(s)-b-aminoisobutyrate
(s)-beta-aminoisobutyrate
(s)-β-aminoisobutyrate
(s)-β-aminoisobutyric acid


S-Methylmalonyl-CoA belongs to the class of organic compounds known as acyl coas. These are organic compounds containing a coenzyme A substructure linked to an acyl chain. S-Methylmalonyl-CoA is slightly soluble (in water) and an extremely strong acidic compound (based on its pKa). S-Methylmalonyl-CoA has been primarily detected in urine. Within the cell, S-methylmalonyl-CoA is primarily located in the cytoplasm, mitochondria and peroxisome. In humans, S-methylmalonyl-CoA is involved in the threonine and 2-oxobutanoate degradation pathway, the propanoate metabolism pathway, and the valine, leucine and isoleucine degradation pathway. S-Methylmalonyl-CoA is also involved in several metabolic disorders, some of which include the isovaleric aciduria pathway, the maple syrup urine disease pathway, isobutyryl-CoA dehydrogenase deficiency, and the 3-methylglutaconic aciduria type III pathway. Methylmalonyl-CoA is an intermediate in the metabolism of Propanoate. It is a substrate for Malonyl-CoA decarboxylase (mitochondrial), Methylmalonyl-CoA mutase (mitochondrial) and Methylmalonyl-CoA epimerase (mitochondrial).


R-Methylmalonyl-CoA belongs to the class of organic compounds known as acyl coas. These are organic compounds containing a coenzyme A substructure linked to an acyl chain. R-Methylmalonyl-CoA is slightly soluble (in water) and an extremely strong acidic compound (based on its pKa). R-Methylmalonyl-CoA has been primarily detected in urine. Within the cell, R-methylmalonyl-CoA is primarily located in the cytoplasm. In humans, R-methylmalonyl-CoA is involved in the threonine and 2-oxobutanoate degradation pathway, the valine, leucine and isoleucine degradation pathway, and the propanoate metabolism pathway. R-Methylmalonyl-CoA is also involved in several metabolic disorders, some of which include the maple syrup urine disease pathway, the 3-methylglutaconic aciduria type IV pathway, 3-methylcrotonyl CoA carboxylase deficiency type I, and 3-hydroxyisobutyric acid dehydrogenase deficiency. Methylmalonyl-CoA is an intermediate in the metabolism of Propanoate. It is a substrate for Malonyl-CoA decarboxylase (mitochondrial), Methylmalonyl-CoA mutase (mitochondrial) and Methylmalonyl-CoA epimerase (mitochondrial).


Cobamamide

Adenosylcobalamin is one of two metabolically active forms synthesized upon ingestion of vitamin B12 and is the predominant form in the liver; it acts as a coenzyme in the reaction catalyzed by methylmalonyl-CoA mutase. A cobalamin (cbl) derivative in which the substituent is deoxyadenosyl. It is one of two metabolically active forms synthesized upon ingestion of vitamin B12 and is the predominant form in the liver; it acts as a coenzyme in the reaction catalyzed by methylmalonyl-CoA mutase (MCM; E.C. 5.4.99.2). Inborn errors of vitamin B12 metabolism are autosomal recessive disorders and have been classified into nine distinct complementation classes. Disorders affecting adenosylcobalamin cause methylmalonic acidemia and metabolic acidosis. Methylmalonyl-CoA mutase catalyzes the conversion of L-methylmalonyl-CoA to succinyl-CoA and uses adenosylcobalamin (AdoCbl) as a cofactor. Cbl must be transported into mitochondria, reduced and adenosylated before it can be utilized by MCM. (PMID: 17011224).


Diguanosine tetraphosphate is a diguanosine polyphosphate. Diguanosine polyphosphates (GpnGs) are found in human platelets, among a number of dinucleoside polyphosphates, which vary with respect to the number of phosphate groups and the nucleoside moieties; not only diguanosine polyphosphates (GpnG) are found, but also mixed dinucleoside polyphosphates containing one adenosine and one guanosine moiety (ApnG). The vasoactive nucleotides that can be detected in human plasma contain shorter (n=2-3) and longer (n=4-6) polyphosphate chains. GpnGs have not yet been characterized so far with respect to their effects on kidney vasculature. (PMID: 11159696, 11682456, 11115507).


dGDP

dGDP is a derivative of the common nucleic acid GTP, or guanosine triphosphate, in which the -OH (hydroxyl) group on the 2' carbon on the nucleotide's pentose has been removed (hence the deoxy- part of the name). Additionally, the diphosphate of the name indicates that one of the phosphoryl groups of GTP has been removed, most likely by hydrolysis (Wikipedia).

2'-deoxy-gdp
2'-deoxyguanosine-5'-diphosphate
5'-dgdp
Deoxyguanosine 5'-diphosphate
Deoxyguanosine diphosphate
Deoxyguanosine-diphosphate
Dgdp
2'-deoxyguanosine 5'-diphosphate
2'-deoxyguanosine 5'-diphosphoric acid
Deoxyguanosine diphosphoric acid


dGTP

Under normal physiologic conditions, deoxyguanosine (dGuo) undergoes phosphorolysis by purine nucleoside phosphorylase (PNP, EC 2.4.2.1, an enzyme involved in the recycling of nucleosides and deoxynucleosides in cellular remodeling). However, when PNP is inhibited, deoxycytidine kinase (dCK, EC 2.7.1.74) shunts unmetabolized dGuo into deoxyguanosine triphosphate (dGTP), which accumulates and blocks DNA synthesis. Deficiency of purine nucleoside phosphorylase results in defective T-cell immunity. A correlation between the degree of T cell inhibition and the level of dCK activity is observed. (PMID: 11287638, 402573).

Deoxyguanosine 5'-triphosphate
2'-deoxyguanosine 5'-triphosphate
2'-deoxyguanosine triphosphate
Deoxyguanosine triphosphate
2'-deoxyguanosine 5'-triphosphoric acid
Deoxyguanosine 5'-triphosphoric acid
Deoxyguanosine triphosphoric acid


2'-Deoxyguanosine 5'-monophosphate is a derivative of the common nucleic acid GTP, or guanosine triphosphate, in which the -OH (hydroxyl) group on the 2' carbon on the nucleotide's pentose has been removed (hence the deoxy- part of the name). Additionally, the diphosphate of the name indicates that two of the phosphoryl groups of GTP have been removed, most likely by hydrolysis (Wikipedia).


Deoxyguanosine

Deoxyguanosine is a nucleoside consisting of the base guanine and the sugar deoxyribose. It is like guanosine, but with one oxygen atom removed. It is a nucleoside component of DNA. Deoxyguanosine can be converted to 8-hydroxy-deoxyguanosine (8-OHdG) due to hydroxyl radical attack at the C8 of guanine. 8-OHdG is a sensitive marker of the DNA damage This damage, if left unrepaired, has been proposed to contribute to mutagenicity and cancer promotion.


Guanine

Guanine is one of the five main nucleobases found in the nucleic acids DNA and RNA. Guanine is a derivative of purine, consisting of a fused pyrimidine-imidazole ring system with conjugated double bonds. Being unsaturated, the bicyclic molecule is planar. The guanine nucleoside is called guanosine. The first isolation of guanine was reported in 1844 from the excreta of sea birds, known as guano, which was used as a source of fertilizer. High affinity binding of guanine nucleotides and the ability to hydrolyze bound GTP to GDP are characteristics of an extended family of intracellular proteins. Guanine nucleotide-binding regulatory proteins may be involved in the activation of phospholipases C and A2 by hormones and other ligands. The binding of hormones to receptors that activate phospholipase C is decreased by guanine nucleotides and these hormones also stimulate a high-affinity GTPase activity in cell membranes. Effects of hormones on phospholipase C activity in cell-free preparations are dependent on the presence of guanine nucleotides. Hypoxanthine-guanine phosphoribosyltransferase (HPRT, EC 2.4.2.8) is a purine salvage enzyme that catalyses the conversion of hypoxanthine and guanine to their respective mononucleotides. Partial deficiency of this enzyme can result in the overproduction of uric acid leading to a severe form of gout, whilst a virtual absence of HPRT activity causes the Lesch-Nyhan syndrome which is characterised by hyperuricaemia, mental retardation, choreoathetosis and compulsive self-mutilation. Peroxynitrite induces DNA base damage predominantly at guanine (G) and 8-oxoguanine (8-oxoG) nucleobases via oxidation reactions. G and 8-oxoG are the most reactive bases toward Peroxynitrite and possibly the major contributors to peroxynitrite-derived genotoxic and mutagenic lesions. The neutral G radical, reacts with NO2 to yield 8-nitroguanine and 5-nitro-4-guanidinohydantoin. (PMID: 16352449, 2435586, 2838362, 1487231).


Guanosine

Guanosine is a nucleoside comprising guanine attached to a ribose (ribofuranose) ring via a beta-N9-glycosidic bond. Guanosine can be phosphorylated to become GMP (guanosine monophosphate), cGMP (cyclic guanosine monophosphate), GDP (guanosine diphosphate), and GTP (guanosine triphosphate) (Wikipedia). This nucleoside exerts important neuroprotective and neuromodulator roles in the central nervous system, which may be related to inhibition of the glutamatergic neurotransmission activity. Guanosine is the specific extracellular guanine-based purines effector and its conversion occurs not only in the central nervous system but also peripherally (PMID: 16325434). Guanosine is found to be associated with purine nucleoside phosphorylase (PNP) deficiency, which is an inborn error of metabolism.


Ribose 1-phosphate is an intermediate in the metabolism of Pyrimidine and the metabolism of Nicotinate and nicotinamide. It is a substrate for Uridine phosphorylase 2, Phosphoglucomutase, Purine nucleoside phosphorylase and Uridine phosphorylase 1. Ribose 1-phosphate can be formed from guanosine through the action of purine nucleoside phosphorylase. Ribose 1-phosphate can also act as a ribose donor in the synthesis of xanthosine as catalyzed by the same enzyme (purine nucleoside phosphorylase). The presence of guanase, which irreversibly converts guanine to xanthine, affects the overall process of guanosine transformation. As a result of this purine pathway, guanosine is converted into xanthosine, thus overcoming the lack of guanosine deaminase in mammals. The activated ribose moiety in Ribose 1-phosphate which stems from the catabolism of purine nucleosides can be transferred to uracil and, in the presence of ATP, used for the synthesis of pyrimidine nucleotides; therefore, purine nucleosides can act as ribose donors for the salvage of pyrimidine bases. (PMID: 9133638).


2-deoxy-D-ribofuranose 1-phosphate

Deoxyribose 1-phosphate belongs to the class of organic compounds known as pentoses. These are monosaccharides in which the carbohydrate moiety contains five carbon atoms. Deoxyribose 1-phosphate is soluble (in water) and a moderately acidic compound (based on its pKa). Within the cell, deoxyribose 1-phosphate is primarily located in the cytoplasm. Deoxyribose 1-phosphate exists in all living organisms, ranging from bacteria to humans. Deoxyribose 1-phosphate participates in a number of enzymatic reactions. In particular, Hypoxanthine and deoxyribose 1-phosphate can be biosynthesized from deoxyinosine through its interaction with the enzyme purine nucleoside phosphorylase. Furthermore, Adenine and deoxyribose 1-phosphate can be biosynthesized from deoxyadenosine through its interaction with the enzyme purine nucleoside phosphorylase. Furthermore, Uracil and deoxyribose 1-phosphate can be biosynthesized from deoxyuridine through its interaction with the enzyme thymidine phosphorylase / uracil phosphorylase. Finally, Thymine and deoxyribose 1-phosphate can be biosynthesized from thymidine; which is catalyzed by the enzyme thymidine phosphorylase / uracil phosphorylase. In humans, deoxyribose 1-phosphate is involved in the thioguanine action pathway, the azathioprine action pathway, the mercaptopurine action pathway, and the purine metabolism pathway. Deoxyribose 1-phosphate is also involved in several metabolic disorders, some of which include the gout or kelley-seegmiller syndrome pathway, purine nucleoside phosphorylase deficiency, UMP synthase deficiency (orotic aciduria), and molybdenum cofactor deficiency. Deoxyribose 1-phosphate is an intermediate in the metabolism of Pyrimidine. It is a substrate for Purine nucleoside phosphorylase and Thymidine phosphorylase.


Xanthine

Xanthine is a purine base found in most body tissues and fluids, certain plants, and some urinary calculi. It is an intermediate in the degradation of adenosine monophosphate to uric acid, being formed by oxidation of hypoxanthine. The methylated xanthine compounds caffeine, theobromine, and theophylline and their derivatives are used in medicine for their bronchodilator effects. (Dorland, 28th ed.).


D-ribofuranose 5-phosphate

D-Ribose 5-phosphate is an important intermediate metabolite in the Pentose phosphate pathway (KEGG, map00030) and in the Purine metabolism pathway (KEGG, map00230). The intracellular ribose 5-phosphate concentration is an important determinant of the rate of de novo purine synthesis. (PMID 6699001).


Glycinamide Ribonucleotide

Glycinamidoribotide conversion to N-formylglycinamide ribonucleotide is the third reaction of the de novo purine biosynthesis, a reaction catalyzed by the enzyme Glycinamide ribonucleotide transformylase (EC 2.1.2.2), with concomitant conversion of 10-formyltetrahydrofolate to tetrahydrofolate. (PMID: 9143358). Glycineamideribotide formation is stimulated by Luteinizing hormone (LH) and Chorionic gonadotropin (HCG) via activation of Glc-6-P-dehydrogenase (EC 1.1.1.49). (PMID: 4366083).


5'-Phosphoribosyl-N-formylglycineamide (also known as FGAR or N-Formyl-GAR) is a substrate for Phosphoribosylformylglycinamidine synthase. It is involved in aminoimidazole ribonucleotide biosynthesis and plays a vital role in purine metabolism as well as the conversion of glutamine to glutamate. 5'-Phosphoribosyl-N-formylglycineamide is described as a glycinamide ribonucleotide having a phosphate group at the 5-position and a formyl group on the glycine nitrogen.


CID 54196400

Phosphoribosylformylglycineamidine, also known as fgam, belongs to the class of organic compounds known as pentose phosphates. These are carbohydrate derivatives containing a pentose substituted by one or more phosphate groups. Phosphoribosylformylglycineamidine is slightly soluble (in water) and a moderately acidic compound (based on its pKa). Phosphoribosylformylglycineamidine exists in all living organisms, ranging from bacteria to humans. In humans, phosphoribosylformylglycineamidine is involved in the mercaptopurine action pathway, the purine metabolism pathway, the azathioprine action pathway, and the thioguanine action pathway. Phosphoribosylformylglycineamidine is also involved in several metabolic disorders, some of which include xanthine dehydrogenase deficiency (xanthinuria), myoadenylate deaminase deficiency, molybdenum cofactor deficiency, and the gout or kelley-seegmiller syndrome pathway. Outside of the human body, phosphoribosylformylglycineamidine can be found in a number of food items such as winter savory, rambutan, mountain yam, and guava. This makes phosphoribosylformylglycineamidine a potential biomarker for the consumption of these food products. 5-Phosphoribosyl-n-formylglycineamidine is a substrate for Glucosamine-6-phosphate isomerase.


5-aminoimidazole ribonucleotide (AIR), is an intermediate of purine nucleotide biosynthesis. It is also the precursor to 4-amino-2-methyl-5-hydroxymethylpyrimidine (HMP), the first product of pyrimidine biosynthesis. This reaction is mediated by the enzyme HMP-P kinase (ThiD). HMP is a precursor of thiamine phosphate (TMP), and subsequently to thiamine pyrophosphate (TPP). TPP is an essential cofactor in all living systems that plays a central role in metabolism. (PMID: 15326535). 5-Aminoimidazole ribonucleotide is a substrate for a number of proteins including: Scaffold attachment factor B2, Multifunctional protein ADE2, Pulmonary surfactant-associated protein B, Tumor necrosis factor receptor superfamily member 25, Pulmonary surfactant-associated protein C, Serine/threonine-protein kinase Chk1, Vinexin, Trifunctional purine biosynthetic protein adenosine-3, Antileukoproteinase 1 and Scaffold attachment factor B.


5-amino-1-(5-phospho-D-ribosyl) imidazole-4-carboxylate is an intermediate in purine metabolism. 5-amino-1-(5-phospho-D-ribosyl) imidazole-4-carboxylate is converted from aminoimidazole ribotide via phosphoribosylaminoimidazole carboxylase [EC: 4.1.1.21].

5-aminoimidazole carboxilic acid ribonucleotice


SAICAR

SAICAR (or (S)-2-[5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxamido]succinate) is a substrate for the multifunctional protein ADE2. SAICAR is an intermediate in purine metabolism. SAICAR is converted from 5-amino-1-(5-phospho-D-ribosyl) imidazole-4-carboxylate via phosphoribosylaminoimidazole-succinocarboxamide synthase (EC: 6.3.2.6) or SAICAR synthase. This enzyme catalyses the seventh step out of ten in the biosynthesis of purine nucleotides. The appearance of succinylaminoimidazolecarboxamide riboside (SAICAriboside) and succinyladenosine (S-Ado) in cerebrospinal fluid, in urine, and, to a lesser extent, in plasma is characteristic of a heritable deficiency known as adenylosuccinate lyase deficiency. Adenylosuccinate lyase deficiency is responsible for a range of symptoms that involve psychomotor retardation, often accompanied by epileptic seizures, and autistic features. When present in sufficiently high levels, SAICAR can act as an oncometabolite, a metabotoxin, and an acidogen. An oncometabolite is a compound that promotes tumour growth and survival. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. As an oncometabolite, high levels of SAICAR stimulate pyruvate kinase isoform M2 and promote cancer cell survival in glucose-limited conditions such as aerobic glycolysis (PMID: 23086999). As an organic acid, SAICAR is associated with acidosis. 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, liver, and kidney abnormalities, seizures, coma, and possibly death. These are also the characteristic symptoms of untreated adenylosuccinate lyase deficiency. Many affected children with organic acidemias experience intellectual disability or delayed development.


AICAR

AICAR also known as ZMP is an analog of AMP that is capable of stimulating AMP-dependent protein kinase activity(AMPK). AICAR is an intermediate in the generation of inosine monophosphate. AICAR is being clinically used to treat and protect against cardiac ischemic injury. AICAR can enter cardiac cells to inhibit adenosine kinase and adenosine deaminase. It enhances the rate of nucleotide re-synthesis increasing adenosine generation from adenosine monophosphate only during conditions of myocardial ischemia. AICAR increases glucose uptake by inducing translocation of GLUT4 and/or by activating the p38 MAPK pathway.


FAICAR

Phosphoribosyl formamidocarboxamide, also known as faicar, belongs to the class of organic compounds known as 1-ribosyl-imidazolecarboxamides. These are organic compounds containing the imidazole ring linked to a ribose ring through a 1-2 bond. Phosphoribosyl formamidocarboxamide is slightly soluble (in water) and a moderately acidic compound (based on its pKa). Within the cell, phosphoribosyl formamidocarboxamide is primarily located in the cytoplasm and mitochondria. Phosphoribosyl formamidocarboxamide exists in all living organisms, ranging from bacteria to humans. In humans, phosphoribosyl formamidocarboxamide is involved in the azathioprine action pathway, the mercaptopurine action pathway, the thioguanine action pathway, and the purine metabolism pathway. Phosphoribosyl formamidocarboxamide is also involved in several metabolic disorders, some of which include xanthine dehydrogenase deficiency (xanthinuria), the gout or kelley-seegmiller syndrome pathway, myoadenylate deaminase deficiency, and adenylosuccinate lyase deficiency. Outside of the human body, phosphoribosyl formamidocarboxamide can be found in a number of food items such as kai-lan, apricot, cupuaçu, and pomes. This makes phosphoribosyl formamidocarboxamide a potential biomarker for the consumption of these food products. This compound is an intermediate in purine metabolism, where it is the byproduct of phosphoribosylaminoimidazolecarboxamide formyltransferase (EC 2.1.2.3) and IMP cyclohydrolase (EC 3.5.4.10). It is also a byproduct of Ligases (EC 6.3.4.-).


xanthosine

Biological Source: Xanthosine is produced by guanine-free mutants of bacteria e.g. Bacillus subtilis, Aerobacter aerogenes. Also reported from seeds of Trifolium alexandrinum Physical Description: Prismatic cryst. (H2O) (Chemnetbase) The deamination product of guanosine. Xanthosine monophosphate is an intermediate in purine metabolism, formed from IMP, and forming GMP.(Wikipedia). Xanthylic acid can be used in quantitative measurements of the Inosine monophosphate dehydrogenase enzyme activities in purine metabolism, as recommended to ensure optimal thiopurine therapy for children with acute lymphoblastic leukaemia (ALL). (PMID: 16725387).


Inosine

Inosine is a purine nucleoside that has hypoxanthine linked by the N9 nitrogen to the C1 carbon of ribose. It is an intermediate in the degradation of purines and purine nucleosides to uric acid and in pathways of purine salvage. It also occurs in the anticodon of certain transfer RNA molecules. (Dorland, 28th ed).


Hypoxanthine

Hypoxanthine is a naturally occurring purine derivative and a reaction intermediate in the metabolism of adenosine and in the formation of nucleic acids by the salvage pathway. Hypoxanthine is also a spontaneous deamination product of adenine. Lesch-Nyhan disease is caused by deficiency of the purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase. (OMIN 308000).


Uric acid

Uric acid is a heterocyclic purine derivative that is the final oxidation product of purine metabolism. It is produced by the enzyme xanthine oxidase, which oxidizes oxypurines such as xanthine into uric acid. In most mammals, except humans and higher primates, the enzyme uricase further oxidizes uric acid to allantoin. Uric acid is also the end product of nitrogen metabolism in birds and reptiles. In such species, it is excreted in feces as a dry mass. Humans produce only small quantities of uric acid with excess accumulation leading to a type of arthritis known as gout. The loss of uricase in higher primates parallels the similar loss of the ability to synthesize ascorbic acid vitamin C. This may be because in higher primates uric acid partially replaces ascorbic acid.


Deoxyinosine

Deoxyinosine is a nucleoside that is formed when hypoxanthine is attached to a deoxyribose ring (also known as a ribofuranose) via a beta-N9-glycosidic bond. Deoxyinosine is found in DNA while Inosine is found in RNA. Inosine is a nucleic acid important for RNA editing. Adenosine deaminase (ADA) catalyzes the conversion of adenosine and deoxyadenosine to inosine and deoxyinosine, respectively. ADA-deficient individuals suffer from severe combined immunodeficiency (SCID) and are unable to produce significant numbers of mature T or B lymphocytes. This occurs as a consequence of the accumulation of ADA substrates or their metabolites. Inosine is also an intermediate in a chain of purine nucleotides reactions required for muscle movements.


Adenine

Adenine is a purine base. Adenine is found in both DNA and RNA. Adenine is a fundamental component of adenine nucleotides. Adenine forms adenosine, a nucleoside, when attached to ribose, and deoxyadenosine when attached to deoxyribose; it forms adenosine triphosphate (ATP), a nucleotide, when three phosphate groups are added to adenosine. Adenosine triphosphate is used in cellular metabolism as one of the basic methods of transferring chemical energy between chemical reactions. Purine inborn errors of metabolism (IEM) are serious hereditary disorders, which should be suspected in any case of neonatal fitting, failure to thrive, recurrent infections, neurological deficit, renal disease, self-mutilation and other manifestations. Investigation usually starts with uric acid (UA) determination in urine and plasma. (OMIM 300322, 229600, 603027, 232400, 232600, 232800, 201450, 220150, 232200, 162000, 164050, 278300). (PMID: 17052198, 17520339).


DEOXYADENOSINE

Deoxyadenosine is a derivative of the nucleoside adenosine. It is composed of adenine attached to a deoxyribose moiety via a N9-glycosidic bond. Deoxyribose differs from ribose by the absence of oxygen in the 3' position of its ribose ring. Deoxyadenosine is a critical component of DNA. When present in sufficiently high levels, deoxyadensoine can act as an immunotoxin and a metabotoxin. An immunotoxin disrupts, limits the function, or destroys immune cells. A metabotoxin is an endogenous metabolite that causes adverse health effects at chronically high levels. Chronically high levels of deoxyadenosine are associated with adenosine deaminase (ADA) deficiency, an inborn error of metabolism. ADA deficiency damages the immune system and causes severe combined immunodeficiency (SCID). People with SCID lack virtually all immune protection from bacteria, viruses, and fungi. They are prone to repeated and persistent infections that can be very serious or life-threatening. These infections are often caused by "opportunistic" organisms that ordinarily do not cause illness in people with a normal immune system. The main symptoms of ADA deficiency are pneumonia, chronic diarrhea, and widespread skin rashes. The mechanism by which dATP functions as an immunotoxin is as follows: because deoxyadenosine is a precursor to dATP, a buildup of dATP in cells inhibits ribonucleotide reductase and prevents DNA synthesis, so cells are unable to divide. Since developing T cells and B cells are some of the most mitotically active cells, they are unable to divide and propagate to respond to immune challenges. High levels of deoxyadenosine also lead to an increase in S-adenosylhomocysteine, which is toxic to immature lymphocytes.


Cyclic AMP

cAMP or cyclic AMP is an adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH. cAMP is synthesized from ATP by adenylate cyclase. Adenylate cyclase is located at the cell membranes. Adenylate cyclase is activated by the hormones glucagon and adrenaline and by G protein. Liver adenylate cyclase responds more strongly to glucagon, and muscle adenylate cyclase responds more strongly to adrenaline. cAMP decomposition into AMP is catalyzed by the enzyme phosphodiesterase.

Adenosine 3,5'-cyclic monophosphoric acid

Adenosine 3',5'-cyclic monophosphoric acid


dADP

dADP belongs to the class of organic compounds known as purine 2'-deoxyribonucleoside diphosphates. These are purine nucleotides with diphosphate group linked to the ribose moiety lacking a hydroxyl group at position 2. dADP is slightly soluble (in water) and a moderately acidic compound (based on its pKa). dADP has been found throughout most human tissues. Within the cell, dADP is primarily located in the mitochondria, nucleus and cytoplasm. In humans, dADP is involved in the purine metabolism pathway, the thioguanine action pathway, the azathioprine action pathway, and the mercaptopurine action pathway. dADP is also involved in several metabolic disorders, some of which include xanthine dehydrogenase deficiency (xanthinuria), adenine phosphoribosyltransferase deficiency (aprt), the xanthinuria type I pathway, and the xanthinuria type II pathway. Deoxyadenosine diphosphate has been identified in the mononuclear cells of a patient affected with in inherited adenosine deaminase deficiency (OMIM 102700) (PMID 6980023), and in in mononuclear cells of hemodialyzed patients. (PMID 11461945).

2'-deoxyadenosine-5'-diphosphate
Deoxyadenosine diphosphate
Dadp


Adenosine is a nucleoside comprised of adenine attached to a ribose (ribofuranose) moiety via a -N9-glycosidic bond. Deoxyadenosine monophosphate is a derivative of the common nucleic acid ATP, or adenosine triphosphate, in which the -OH (hydroxyl) group on the 2' carbon on the nucleotide's pentose has been removed (hence the deoxy- part of the name). Additionally, the monophosphate of the name indicates that two of the phosphoryl groups of GTP have been removed, most likely by hydrolysis. Deoxyadenosine monophosphate is abbreviated dAMP. (Wikipedia).

2'-deoxyadenosine 5'-(dihydrogen phosphoric acid)


dATP

Deoxyadenosine triphosphate (dATP) is a purine nucleoside triphosphate used in cells for DNA synthesis. A nucleoside triphosphate is a molecule type that contains a nucleoside with three phosphates bound to it. dATP contains the sugar deoxyribose, a precursor to DNA synthesis whereby the two existing phosphate groups are cleaved with the remaining deoxyadenosine monophosphate being incorporated into DNA during replication. Due to its enzymatic incorporation into DNA, photoreactive dATP analogs such as N6-[4-azidobenzoyl–(2-aminoethyl)]-2′-deoxyadenosine-5′-triphosphate (AB-dATP) and N6-[4-[3-(trifluoromethyl)-diazirin-3-yl]benzoyl-(2-aminoethyl)]-2′-deoxyadenosine-5′-triphosphate (DB-dATP) have been used for DNA photoaffinity labeling. When present in sufficiently high levels, dATP can act as an immunotoxin and a metabotoxin. An immunotoxin disrupts, limits the function, or destroys immune cells. A metabotoxin is an endogenous metabolite that causes adverse health effects at chronically high levels. Chronically high levels of deoxyadenosine triphosphate are associated with adenosine deaminase (ADA) deficiency, an inborn error of metabolism. ADA deficiency damages the immune system and causes severe combined immunodeficiency (SCID). People with SCID lack virtually all immune protection from bacteria, viruses, and fungi. They are prone to repeated and persistent infections that can be very serious or life-threatening. These infections are often caused by "opportunistic" organisms that ordinarily do not cause illness in people with a normal immune system. The main symptoms of ADA deficiency are pneumonia, chronic diarrhea, and widespread skin rashes. The mechanism by which dATP functions as an immunotoxin is as follows: a buildup of dATP in cells inhibits ribonucleotide reductase and prevents DNA synthesis, so cells are unable to divide. Since developing T cells and B cells are some of the most mitotically active cells, they are unable to divide and propagate to respond to immune challenges.

2'-Deoxy-5'-ATP
2'-Deoxy-ATP
2'-Deoxyadenosine 5'-triphosphate
2'-Deoxyadenosine triphosphate
Deoxy-ATP
Deoxyadenosine 5'-triphosphate
Deoxyadenosine triphosphate
Deoxyadenosine-triphosphate
dATP
2'-Deoxyadenosine 5'-triphosphoric acid
Deoxyadenosine 5'-triphosphoric acid
Deoxyadenosine triphosphoric acid


2',3'-Cyclic GMP is a cyclic guanosine derivative that is a precursor to 3'-GMP. The enzyme 2'3'-cyclic-nucleotide 2'-phosphodiesterase (E.C. 3.1.4.16) catalyses the hydrolysis of both 2',3'-cyclic AMP and 2',3'-cyclic GMP into 3'-AMP and 3'-GMP, respectively, at the 3'-terminal of RNA. 2',3'-cyclic phosphate termini are produced, as either intermediates or final products, during RNA cleavage by many different endoribonucleases. The enzyme RNA 3'-phosphate cyclase also converts the 3'-terminal phosphate in RNA into the 2',3'-cyclic phosphodiester in the ATP-dependent reaction which involves formation of the covalent cyclase-AMP and the RNA-N3' pp5' A intermediates (PMID: 10397337). This enzyme could be involved in the maintenance of cyclic ends in tRNA splicing intermediates or in the cyclization of the 3' end of U6 snRNA (PMID: 9184239). Guanosine-2',3'-cyclic phosphate is capable of blocking DNA synthesis in vitro (PMID: 7528887). 2', 3'-cGMP seems to preferentially stimulate mature T-cells while 3', 5'-cGMP preferentially acts on B-cells (PMID: 163786).

Guanosine cyclic 2',3'-(hydrogen phosphate)

Cyclic guanosine 2',3'-monophosphoric acid

Guanosine 2',3'-cyclic monophosphoric acid

Guanosine cyclic 2',3'-(hydrogen phosphoric acid)


IDP

IDP, also known as riboxin or 5'-idp, belongs to the class of organic compounds known as purine ribonucleoside diphosphates. These are purine ribobucleotides with diphosphate group linked to the ribose moiety. IDP is slightly soluble (in water) and a moderately acidic compound (based on its pKa). Within the cell, IDP is primarily located in the mitochondria and nucleus. IDP exists in all living organisms, ranging from bacteria to humans. In humans, IDP is involved in the thioguanine action pathway, the azathioprine action pathway, the purine metabolism pathway, and the mercaptopurine action pathway. IDP is also involved in several metabolic disorders, some of which include the xanthinuria type I pathway, the gout or kelley-seegmiller syndrome pathway, xanthine dehydrogenase deficiency (xanthinuria), and the AICA-ribosiduria pathway. IDP is an inosine nucleotide containing a pyrophosphate group esterified to C5 of the sugar moiety.

5'-idp
Idp
Inosine 5'-(trihydrogen diphosphate)
Inosine 5'-(trihydrogen pyrophosphate)
Inosine 5'-diphosphate
Inosine 5'-pyrophosphate
Inosine diphosphate
Inosine pyrophosphate
Riboxin
Riboxine


ITP

Inosine triphosphate (ITP) is an intermediate in the purine metabolism pathway. Relatively high levels of ITP in red cells are found in individuals as result of deficiency of inosine triphosphatase (EC 3.1.3.56, ITPase) ITPase is a cytosolic nucleoside triphosphate pyrophosphohydrolase specific for ITP catalysis to inosine monophosphate (IMP) and deoxy-inosine triphosphate (dITP) to deoxy-inosine monophosphate. ITPase deficiency is not associated with any defined pathology other than the characteristic and abnormal accumulation of ITP in red blood cells. Nevertheless, ITPase deficiency may have pharmacogenomic implications, and the abnormal metabolism of 6-mercaptopurine in ITPase-deficient patients may lead to thiopurine drug toxicity. ITPase's function is not clearly understood but possible roles for ITPase could be to prevent the accumulation of rogue nucleotides which would be otherwise incorporated into DNA and RNA, or compete with nucleotides such as GTP in signalling processes. (PMID : 170291, 1204209, 17113761, 17924837).


orazamide

5-Aminoimidazole-4-carboxamide is an imidazole derivative which is a metabolite of the antineoplastic agents BIC and DIC. By itself, or as the ribonucleotide, it is used as a condensation agent in the preparation of nucleosides and nucleotides. Compounded with orotic acid, it is used to treat liver diseases. -- Pubchem.


disulfane

Disulfides, also known as HSSH or hydrogen sulfide, belongs to the class of inorganic compounds known as other non-metal sulfides. These are inorganic compounds containing a sulfur atom of an oxidation state of -2, in which the heaviest atom bonded to the oxygen belongs to the class of other non-metals. Outside of the human body, disulfides can be found in soft-necked garlic. This makes disulfides a potential biomarker for the consumption of this food product.


Pyridoxamine

The 4-aminomethyl form of vitamin B6. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate. -- Pubchem; Pyridoxamine is one of the compounds that can be called vitamin B6, along with Pyridoxal and Pyridoxine. -- Wikipedia.


vitamin B6

The 4-methanol form of vitamin B6 which is converted to pyridoxal phosphate which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. Although pyridoxine and Vitamin B6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading (EE Snell; Ann NY Acad Sci, vol 585 pg 1, 1990). Pyridoxine is one of the compounds that can be called vitamin B6. Pyridoxine assists in the balancing of sodium and potassium as well as promoting red blood cell production. It is linked to cancer immunity and helps fight the formation of homocysteine. It has been suggested that Pyridoxine might help children with learning difficulties, and may also prevent dandruff, eczema, and psoriasis. In addition, pyridoxine can help balance hormonal changes in women and aid in immune system. Lack of pyridoxine may cause anemia, nerve damage, seizures, skin problems, and sores in the mouth. -- Wikipedia Deficiency, though rare because of widespread distribution in foods, leads to the development of peripheral neuritis in adults and affects the central nervous system in children (DOSE - 3rd edition).


Pyridoxic Acid

4-Pyridoxic acid is the catabolic product of vitamin B6 (also known as pyridoxine, pyridoxal and pyradoxamine) which is excreted in the urine. Urinary levels of 4-pyridoxic acid are lower in females than in males and will be reduced in persons with riboflavin deficiency. 4-Pyridoxic acid is formed by the action of aldehyde oxidase I (an endogenous enzyme) and by microbial enzymes (pyridoxal 4-dehydrogenase), an NAD-dependent aldehyde dehydrogenase. 4-pyridoxic acid can be further broken down by the gut microflora via 4-pyridoxic acid dehydrogenase. This enzyme catalyzes the four electron oxidation of 4-pyridoxic acid to 3-hydroxy-2-methylpyridine-4,5-dicarboxylate, using nicotinamide adenine dinucleotide as a cofactor.


2-Methyl-3-hydroxy-5-formylpyridine-4-carboxylate is an intermediate in vitamin B6 metabolism(KEGG ID C06050). It is the 4th to last step in the synthesis of succinate semialdehyde, which is an intermediate in butanoate metabolism. 2-Methyl-3-hydroxy-5-formylpyridine-4-carboxylate is converted from 4-pyridoxate and is then converted to 3-hydroxy-2-methylpyridine-4,5-dicarboxylate.


ICHIBA ACID

3-Hydroxy-2-methylpyridine-4,5-dicarboxylate is an intermediate in vitamin B6 metabolism(KEGG ID C04604). It is the third to last step in the synthesis of succinate semialdehyde, which is an intermediate in butanoate metabolism. 3-Hydroxy-2-methylpyridine-4,5-dicarboxylate is generated from 2-Methyl-3-hydroxy-5-formylpyridine-4-carboxylate and is then converted to 3-hydroxy-2-methylpyridine-5-carboxylate.


glycolaldehyde

Glycolaldehyde (HOCH2-CH=O, IUPAC name 2-hydroxyethanal) is a type of diose (2-carbon monosaccharide). Glycolaldehyde is readily converted to acetyl coenzyme A. It has an aldehyde and a hydroxyl group. However, it is not actually a sugar, because there is only one hydroxyl group. Glycolaldehyde is formed from many sources, including the amino acid glycine and from purone catabolism. It can form by action of ketolase on fructose 1,6-bisphosphate in an alternate glycolysis pathway. This compound is transferred by thiamin pyrophosphate during the pentose phosphate shunt.

Glycolaldehyde
2-hydroxyacetaldehyde
2-hydroxyethanal
2-oh-acetaldehyde
2-oxoethanol
Diose
Glycolic aldehyde
Glycollaldehyde
Hydroxyacetaldehyde
Hydroxyethanal
Methylol formaldehyde
Methylolformaldehyde
Monomethylolformaldehyde
Glycoaldehyde


Pyridoxine phosphate

Pyridoxine 5-phosphate, also known as pyridoxine phosphoric acid or pyridoxine-5P, belongs to the class of organic compounds known as pyridoxine-5'-phosphates. These are pyridoxines that carry a phosphate group at the 5-position. Pyridoxine 5-phosphate is slightly soluble (in water) and a moderately acidic compound (based on its pKa). Pyridoxine 5-phosphate has been primarily detected in blood. Within the cell, pyridoxine 5-phosphate is primarily located in the cytoplasm. Pyridoxine 5-phosphate exists in all living organisms, ranging from bacteria to humans. In humans, pyridoxine 5-phosphate is involved in the vitamin B6 metabolism pathway. Pyridoxine 5-phosphate is also involved in the metabolic disorder called the hypophosphatasia pathway. 5-phosphate is a substrate for pyridoxine-5-phosphate oxidase and pyridoxal kinase.

5-hydroxy-6-methyl-3,4-pyridinedimethanol alpha( 3)-(dihydrogen phosphate)


Vitamin B6 is a water-soluble compound that was discovered in 1930s during nutrition studies on rats. The vitamin was named pyridoxine to indicate its structural homology to pyridine. Later it was shown that vitamin B6 could exist in two other, slightly different, chemical forms, termed pyridoxal and pyridoxamine. All three forms of vitamin B6 are precursors of an activated compound known as pyridoxal 5-phosphate (PLP), which plays a vital role as the cofactor of a large number of essential enzymes in the human body. Vitamin B6 is a water-soluble vitamin. The three major forms of vitamin B6 are pyridoxine (also known as pyridoxol), pyridoxal, and pyridoxamine, which are all converted in the liver to pyridoxal 5-phosphate (PLP) a cofactor in many reactions of amino acid metabolism. PLP also is necessary for the enzymatic reaction governing the release of glucose from glycogen.

Pyridoxamine 5'-phosphate
Pyridoxamine 5-phosphate
Pyridoxamine 5-phosphoric acid
Pyridoxamine 5'-phosphoric acid


Lactic acid

Lactic acid is an organic acid. It is a chiral molecule, consisting of two optical isomers, L-lactic acid and D-lactic acid, with the L-isomer being the most common in living organisms. Lactic acid plays a role in several biochemical processes and is produced in the muscles during intense activity. In animals, L-lactate is constantly produced from pyruvate via the enzyme lactate dehydrogenase (LDH) in a process of fermentation during normal metabolism and exercise. It does not increase in concentration until the rate of lactate production exceeds the rate of lactate removal. This is governed by a number of factors, including monocarboxylate transporters, lactate concentration, the isoform of LDH, and oxidative capacity of tissues. The concentration of blood lactate is usually 1-2 mmol/L at rest, but can rise to over 20 mmol/L during intense exertion. There are some indications that lactate, and not glucose, is preferentially metabolized by neurons in the brain of several mammalian species, including mice, rats, and humans. Glial cells, using the lactate shuttle, are responsible for transforming glucose into lactate, and for providing lactate to the neurons. Lactate measurement in critically ill patients has been traditionally used to stratify patients with poor outcomes. However, plasma lactate levels are the result of a finely tuned interplay of factors that affect the balance between its production and its clearance. When the oxygen supply does not match its consumption, organisms adapt in many different ways, up to the point when energy failure occurs. Lactate, being part of the adaptive response, may then be used to assess the severity of the supply/demand imbalance. In such a scenario, the time to intervention becomes relevant: early and effective treatment may allow tissues and cells to revert to a normal state, as long as the oxygen machinery (i.e. mitochondria) is intact. Conversely, once the mitochondria are deranged, energy failure occurs even in the presence of normoxia. The lactate increase in critically ill patients may, therefore, be viewed as an early marker of a potentially reversible state (PMID: 16356243). When present in sufficiently high levels, lactic acid can act as an oncometabolite, an immunosuppressant, an acidogen, and a metabotoxin. An oncometabolite is a compound that promotes tumor growth and survival. An immunosuppressant reduces or arrests the activity of the immune system. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of lactic acid are associated with at least a dozen inborn errors of metabolism, including 2-methyl-3-hydroxybutyryl CoA dehydrogenase deficiency, biotinidase deficiency, fructose-1,6-diphosphatase deficiency, glycogen storage disease type 1A (GSD1A) or Von Gierke disease, glycogenosis type IB, glycogenosis type IC, glycogenosis type VI, Hers disease, lactic acidemia, Leigh syndrome, methylmalonate semialdehyde dehydrogenase deficiency, pyruvate decarboxylase E1 component deficiency, pyruvate dehydrogenase complex deficiency, pyruvate dehydrogenase deficiency, and short chain acyl CoA dehydrogenase deficiency (SCAD deficiency). Locally high concentrations of lactic acid or lactate are found near many tumors due to the upregulation of lactate dehydrogenase (PMID: 15279558). Lactic acid produced by tumors through aerobic glycolysis acts as an immunosuppressant and tumor promoter (PMID: 23729358). Indeed, lactic acid has been found to be a key player or regulator in the development and malignant progression of a variety of cancers (PMID: 22084445). A number of studies have demonstrated that malignant transformation is associated with an increase in aerobic cellular lactate excretion. Lactate concentrations in various carcinomas (e.g. uterine cervix, head and neck, colorectal region) at first diagnosis of the disease, can be relatively low or extremely high (up to 40 µmol/g) in different individual tumors or within the same lesion (PMID: 15279558). High molar concentrations of lactate are correlated with a high incidence of distant metastasis. Low lactate tumors (< median of approximately 8 µmol/g) are associated with both an overall longer and disease-free survival compared to high lactate lesions (lactate > approximately 8 µmol/g). Lactate-induced secretion of hyaluronan by tumor-associated fibroblasts creates a milieu favourable for cell migration and metastases (PMID: 22084445). An acidic environment (pH 6-6.5), which is common in many tumors, allows tumor cells to evade the immune response, and therefore allows them to grow unchecked. Locally high concentrations of lactic acid are known to markedly impede the function of normal immune cells and will lead to a loss of T-cell function of human tumor-infiltrating lymphocytes (PMID: 22084445). Lactic acid is also an organic acid and acts as a general acidogen. 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.

(+)-lactate
(+)-lactic acid
(s)-(+)-2-hydroxypropanoate
(s)-(+)-2-hydroxypropanoic acid
(s)-2-hydroxypropanoate
(s)-2-hydroxypropanoic acid
(s)-2-hydroxypropionate
(s)-2-hydroxypropionic acid
(s)-2-hydroxy-propanoate
(s)-2-hydroxy-propanoic acid
(s)-lactate
(s)-lactic acid
(alpha)-lactate
(alpha)-lactic acid
1-hydroxyethane 1-carboxylate
1-hydroxyethane 1-carboxylic acid
1-hydroxyethanecarboxylate
1-hydroxyethanecarboxylic acid
2-hydroxypropanoate
2-hydroxypropanoic acid
2-hydroxypropionate
L-(+)- lactic acid
L-2-hydroxypropanoate
L-2-hydroxypropanoic acid
Lactate
Lactic acid
Milk acid
Sarcolactic acid
A-hydroxypropanoate
A-hydroxypropanoic acid
A-hydroxypropionate
A-hydroxypropionic acid
Alpha-hydroxypropanoate
Alpha-hydroxypropanoic acid
Alpha-hydroxypropionate
Alpha-hydroxypropionic acid
(s)-(+)-lactic acid
L-(+)-alpha-hydroxypropionic acid
L-(+)-lactic acid
L-lactic acid
L-milchsaeure


D-Lactaldehyde

D- and L-lactaldehyde are also good substrates for aldose reductase. The aldose reductase-catalyzed reduction of methylglyoxal produces 95% acetol, 5% D-lactaldehyde. (PMID: 1537826). D-lactaldehyde is an intermediate in the pyruvate metabolic pathway. Pyruvaldehyde is irreversibly produced from D-lactaldehyde via the enzyme glyoxylate reductase (NADP+, Swiss-Prot: Q5T945).


Lactaldehyde

L-lactaldehyde is an intermediate metabolite in the pyruvate metabolism pathway. L-lactaldehyde is irreversibly produced from pyruvaldehyde via the enzyme aldehyde reductase (EC:1.1.1.21) which is then irreversibly converted to propylene glycol via aldehyde reductase (EC:1.1.1.21).


Hydrogen

Hydrogen is a colorless, odorless, nonmetallic, tasteless, highly flammable diatomic gas with the molecular formula H2. With an atomic weight of 1.00794, hydrogen is the lightest element. Besides the common H1 isotope, hydrogen exists as the stable isotope Deuterium and the unstable, radioactive isotope Tritium. Hydrogen is the most abundant of the chemical elements, constituting roughly 75% of the universe's elemental mass. Hydrogen can form compounds with most elements and is present in water and most organic compounds. It plays a particularly important role in acid-base chemistry, in which many reactions involve the exchange of protons between soluble molecules. Oxidation of hydrogen, in the sense of removing its electron, formally gives H+, containing no electrons and a nucleus which is usually composed of one proton. That is why H+ is often called a proton. This species is central to discussion of acids. Under the Bronsted-Lowry theory, acids are proton donors, while bases are proton acceptors. A bare proton H+ cannot exist in solution because of its strong tendency to attach itself to atoms or molecules with electrons. However, the term 'proton' is used loosely to refer to positively charged or cationic hydrogen, denoted H+. H2 is a product of some types of anaerobic metabolism and is produced by several microorganisms, usually via reactions catalyzed by iron- or nickel-containing enzymes called hydrogenases. These enzymes catalyze the reversible redox reaction between H2 and its component two protons and two electrons. Creation of hydrogen gas occurs in the transfer of reducing equivalents produced during pyruvate fermentation to water.

Dihydrogen
Hydrogen
Hydrogen cation
Hydrogen gas
Hydrogen ion
Hydronium
Proton
E 949
E-949
E949
H2
Molecular hydrogen


Propylene glycol

Propylene glycol (1,2-propanediol) is an organic compound (a diol alcohol), usually a tasteless, odorless, and colorless clear oily liquid that is hygroscopic and miscible with water, acetone, and chloroform. It is manufactured by the hydration of propylene oxide. Propylene glycol is used as a solvent for intravenous, oral, and topical pharmaceutical preparations It is generally considered safe. However in large doses it can be toxic, especially if given over a short period of time. Intravenous lorazepam contains the largest amount of propylene glycol of commonly used drugs. In adults with normal liver and kidney function, the terminal half-life of propylene glycol ranges from 1.4 to 3.3 hours. Propylene glycol is metabolized by the liver to form lactate, acetate, and pyruvate. The nonmetabolized drug is excreted in the urine mainly as the glucuronide conjugate, approximately 12 to 45 percent is excreted unchanged in urine. Renal clearance decreases as the dose administered increases (390 ml/minute/173 m2 at a dose of 5 g/day but only 144 ml/minute/173 m2 at a dose of 21 g/day). These data suggest that renal clearance declines at higher propylene glycol doses because of saturation of proximal tubular secretion of the drug. As an acceptable level of propylene glycol has not been defined, the clinical implication of a propylene glycol level is unclear. The World Health Organization (WHO) recommends a maximum consumption of 25 mg/kg/day (1.8 g/day for a 75 kg male) of propylene glycol when used as a food additive, but this limit does not address its use as a drug solvent. No maximum dose is recommended in the literature for intravenous therapy with propylene glycol. Intoxication occurs at much higher doses than the WHO dose limit and is exclusive to pharmacologic exposure. Propylene glycol toxicity includes development of serum hyperosmolality, lactic acidosis, and kidney failure. It has been suggested that proximal tubular necrosis is the cause of acute kidney injury from propylene glycol. Along these lines, proximal tubular cell injury occurs in cultured human cells exposed to propylene glycol. Acute tubular necrosis was described with propylene glycol toxicity in a case of concomitant administration of intravenous lorazepam and trimethoprim sulfamethoxazole. Propylene glycol induced intoxication can also mimic sepsis or systemic inflammatory response syndrome (SIRS). Patients suspected of having sepsis with negative cultures should be evaluated for propylene glycol toxicity if they have been exposed to high dose lorazepam or other medications containing this solvent. (PMID: 17555487).

(rs)-1,2-propanediol
1,2-(rs)-propanediol
1,2-dihydroxypropane
1,2-propanediol
1,2-propylene glycol
1,2-propylenglykol
2,3-propanediol
2-hydroxypropanol
Aliphatic alcohol
Chilisa fe
Dl-1,2-propanediol
Dl-propylene glycol
Dowfrost
Glycol
Ilexan p
Inhibited 1,2-propylene glycol
Isopropylene glycol
Methyl glycol
Methylethyl glycol
Methylethylene glycol
Monopropylene glycol
Prolugen
Propane-1,2-diol
Propanediol
Propylene glycol
Propylene glycol usp
Propylenglycol
Sentry propylene glycol
Sirlene
Solar winter ban
Solargard p
Trimethyl glycol
Ucar 35
A-propylene glycol
Alpha-propylene glycol


The acetyl thioester of the reduced lipoyllysine residue in dihydrolipoyllysine-residue acetyltransferase (EC2.3.1.12). S-Acetyldihydrolipoamide-E is a reactant or product of enzyme EC 1.2.4.1. S-Acetyldihydrolipoamide-E is a reactant or product of enzyme EC 2.3.1.12. (PubChem sid=47205563).


Malonyl-CoA

Malonyl-CoA, also known as malonyl CoA or CoA, malonyl, belongs to the class of organic compounds known as acyl coas. These are organic compounds containing a coenzyme A substructure linked to an acyl chain. Malonyl-CoA is slightly soluble (in water) and an extremely strong acidic compound (based on its pKa). Malonyl-CoA has been found throughout most human tissues, and has also been primarily detected in urine. Within the cell, malonyl-CoA is primarily located in the mitochondria, peroxisome and cytoplasm. In humans, malonyl-CoA is involved in fatty acid biosynthesis pathway, the pyruvate metabolism pathway, and the propanoate metabolism pathway. Malonyl-CoA is also involved in several metabolic disorders, some of which include the primary hyperoxaluria II, PH2 pathway, pyruvate decarboxylase E1 component deficiency (pdhe1 deficiency), malonyl-CoA decarboxylase deficiency, and pyruvate dehydrogenase complex deficiency. Malonyl-CoA is a coenzyme A derivative which plays a key role in the fatty acid synthesis in the cytoplasmic and microsomal systems.

Malonyl coa
Malonyl coenzyme a
Malonyl-coa
Malonyl-coenzyme a
Omega-carboxyacyl-coa
Omega-carboxyacyl-coenzyme a
S-(hydrogen malonyl)coenzyme a
S-(hydrogen propanedioate
S-(hydrogen propanedioate) coa
S-(hydrogen propanedioate) coenzyme a
S-(hydrogen propanedioic acid


Acetylphosphate

Acetylphosphate or actyl phosphate is a compound involved in taurine and hypotaurine metabolism as well as pyruvate metabolism. It is generated from sulfoacetaldehyde, converted to acetyl-CoA and acetate via phosphate acetyltransferase (EC:2.3.1.8) and acetate kinase (EC:2.7.2.1) respectively. It is also an intermediate in pyruvate metabolism. It is generated from pyruvate and the formation is catalyzed by pyruvate oxidase (EC:1.2.3.3).

Acetyl phosphate
Acetyl-p
Acetylphosphate


Acetyl adenylate is an intermediate in acetyl-CoA synthesis. It is converted from acetate via the enzyme acetyl-CoA synthetase. It is involved in the non-enzymatic acetylation of histones in chromatin (PMID:8619849). In microbes acetyl adenylate also plays a role in the direction of flagellar rotation (PMID:2901103).


beta-D-glucose 6-phosphate

Beta-D-Glucose 6 phosphate (b-G6P) is the beta-anomer of glucose-6-phosphate. There are two anomers of glucose 6 phosphate, the alpha anomer and the beta anomer. Specifically, beta-D-Glucose 6-phosphate is glucose sugar phosphorylated on carbon 6. It is a very common metabolite in cells as the vast majority of glucose entering a cell will become phosphorylated in this way. The primary reason for the immediate phosphorylation of glucose is to prevent diffusion out of the cell. The phosphorylation adds a charged phosphate group so the glucose 6-phosphate cannot easily cross the cell membrane. b-G6P is involved in the glycolysis, gluconeogenesis, pentose phosphate, and glycogen and sucrose metabolic pathways [Kegg ID: C01172]. Beta-D-Glucose 6 phosphate can be generated through beta-D-fructose phosphate or alpha-D-glucose 6 phosphate (via glucose-6-phosphate isomerase) or beta-D glucose (via hexokinase). It can then be sent off to the pentose phosphate pathway which generates the useful cofactor NADPH as well as ribulose 5-phosphate, a carbon source for the synthesis of other molecules. Alternately if the cell needs energy or carbon skeletons for synthesis then glucose 6-phosphate is targeted for glycolysis. A third route is to have glucose 6 phosphate stored or converted to glycogen, especially if blood glucose levels are high.

B-d-glucose 6-(dihydrogen phosphoric acid)

Beta-d-glucose 6-(dihydrogen phosphoric acid)

β-d-glucose 6-(dihydrogen phosphoric acid)


Gluconolactone

Gluconolactone is a lactone or oxidized derivative of glucose. Gluconolactone is a polyhydroxy acid (PHA) that is capable of chelating metals and may also function by scavenging free radicals, thereby protecting skin from some of the damaging effects of UV radiation. Also used as a pheromone by the oriental cockroach.


6-phospho-D-gluconic acid

6-Phosphogluconic acid, also known as 6-phospho-D-gluconate or gluconate 6-phosphate, belongs to the class of organic compounds known as monosaccharide phosphates. These are monosaccharides comprising a phosphated group linked to the carbohydrate unit. 6-Phosphogluconic acid is soluble (in water) and a moderately acidic compound (based on its pKa). 6-Phosphogluconic acid has been found in human adipose , epidermis and prostate tissues, and has also been detected in multiple biofluids, such as saliva and blood. Within the cell, 6-phosphogluconic acid is primarily located in the endoplasmic reticulum. 6-Phosphogluconic acid exists in all living organisms, ranging from bacteria to humans. 6-Phosphogluconic acid participates in a number of enzymatic reactions. In particular, 6-Phosphogluconic acid can be converted into D-ribulose 5-phosphate; which is catalyzed by the enzyme 6-phosphogluconate dehydrogenase, decarboxylating. In addition, 6-Phosphogluconic acid can be biosynthesized from 6-phosphonoglucono-D-lactone through the action of the enzyme 6-phosphogluconolactonase. In humans, 6-phosphogluconic acid is involved in the pentose phosphate pathway. 6-Phosphogluconic acid is also involved in several metabolic disorders, some of which include cancer (via the Warburg effect), ribose-5-phosphate isomerase deficiency, glucose-6-phosphate dehydrogenase deficiency, and transaldolase deficiency. Outside of the human body, 6-phosphogluconic acid can be found in a number of food items such as other soy product, cucumber, persimmon, and mamey sapote. This makes 6-phosphogluconic acid a potential biomarker for the consumption of these food products. Intermediate in the Pentose phosphate pathway (KEGG).

D-gluconic acid 6-(dihydrogen phosphate)


D-ribulose 5-phosphate

D-Ribulose 5-phosphate belongs to the class of organic compounds known as pentose phosphates. These are carbohydrate derivatives containing a pentose substituted by one or more phosphate groups. D-Ribulose 5-phosphate is soluble (in water) and a moderately acidic compound (based on its pKa). D-Ribulose 5-phosphate has been found in human prostate tissue, and has also been detected in multiple biofluids, such as saliva and blood. Within the cell, D-ribulose 5-phosphate is primarily located in the endoplasmic reticulum. D-Ribulose 5-phosphate exists in all living organisms, ranging from bacteria to humans. D-Ribulose 5-phosphate participates in a number of enzymatic reactions. In particular, D-Ribulose 5-phosphate can be converted into D-arabinose 5-phosphate through its interaction with the enzymes D-arabinose 5-phosphate isomerase and D-arabinose 5-phosphate isomerase 2. In addition, D-Ribulose 5-phosphate can be biosynthesized from 6-phosphogluconic acid; which is catalyzed by the enzyme 6-phosphogluconate dehydrogenase, decarboxylating. In humans, D-ribulose 5-phosphate is involved in the pentose phosphate pathway. D-Ribulose 5-phosphate is also involved in several metabolic disorders, some of which include ribose-5-phosphate isomerase deficiency, transaldolase deficiency, cancer (via the Warburg effect), and glucose-6-phosphate dehydrogenase deficiency. D-Ribulose 5-phosphate is a metabolite in the Pentose phosphate pathway, Pentose and glucuronate interconversions, and in the Riboflavin metabolism (KEGG).

D-ribulose 5-phosphate
Erythro-pentulose 5-phosphate
Ribulose 5-phosphate
Ribulose phosphate
Alpha-d-ribose 5-phosphate


D-ribofuranose

D-Ribose, commonly referred to as simply ribose, is a five-carbon sugar found in all living cells. Ribose is not an essential nutrient because it can be synthesized by almost every tissue in the body from other substances, such as glucose. It is vital for life as a component of DNA, RNA, ATP, ADP, and AMP. In nature, small amounts of ribose can be found in ripe fruits and vegetables. Brewer's yeast, which has a high concentration of RNA, is another rich source of ribose. D-ribose is also a component of many so-called energy drinks and anti-ageing products available on the market today. Ribose is a structural component of ATP, which is the primary energy source for exercising muscle. The adenosine component is an adenine base attached to the five-carbon sugar ribose. ATP provides energy to working muscles by releasing a phosphate group, hence becoming ADP, which in turn may release a phosphate group, then becoming AMP. During intense muscular activity, the total amount of ATP available is quickly depleted. In an effort to correct this imbalance, AMP is broken down in the muscle and secreted from the cell. Once the breakdown products of AMP are released from the cell, the energy potential (TAN pool) of the muscle is reduced and ATP must then be reformed using ribose. Ribose helps restore the level of adenine nucleotides by bypassing the rate-limiting step in the de novo (oxidative pentose phosphate) pathway, which regenerates phosphoribosyl pyrophosphate (PRPP), the essential precursor for ATP. If ribose is not readily available to a cell, glucose may be converted to ribose. Ribose supplementation has been shown to increase the rate of ATP resynthesis following intense exercise. The use of ribose in men with severe coronary artery disease resulted in improved exercise tolerance. Hence, there is interest in the potential of ribose supplements to boost muscular performance in athletic activities (PMID: 17618002, Curr Sports Med Rep. 2007 Jul;6(4):254-7.).

D-Ribofuranoside D-Ribofuranose Ribofuranoside Ribofuranose Ribose


Xylulose 5-phosphate (Xu-5-P) is a metabolite of the hexose monophosphate pathway that activates protein phosphatase 2A to mediate the acute effects of carbohydrate feeding on the glycolytic pathway, as well as the coordinate long-term control of the enzymes required for fatty acid and triglyceride synthesis. Xu-5-P is the signal for the coordinated control of lipogenesis. Feeding carbohydrate causes levels of liver glucose, Glucose-6-phosphate (Glc-6-P), and Fructose-6-phosphate (Fru-6-P) to rise. Elevation of Fru-6-P leads to elevation of Xu-5-P in reactions catalyzed by the near-equilibrium isomerases of the nonoxidative portion of the hexose monophosphate pathway (ribulose 5-phosphate (Ru5P) epimerase [EC 5.1.3.1], ribose 5-phosphate (Rib5P) isomerase [EC 5.3.1.6], transaldolase [EC 2.2.1.2], and transketolase [EC 2.2.1.1]). The elevation of Xu-5-P is the coordinating signal that both acutely activates phosphofructokinase [PFK; EC 2.7.1.11] in glycolysis and promotes the action of the transcription factor carbohydrate responsive element binding protein (ChREBP) to increase transcription of the genes for the enzymes of lipogenesis, the hexose monophosphate shunt, and glycolysis, all of which are required for the de novo synthesis of fat. (PMID 12721358).


sedoheptulose 7-phosphate

D-Sedoheptulose 7-phosphate is an intermediate of the Pentose phosphate pathway (PPP) that has two functions: the generation of NADPH for reductive syntheses and oxidative stress responses within cells, and the formation of ribose residues for nucleotide and nucleic acid biosynthesis. (PMID 16055050)It is formed by transketolase and acted upon (degraded) by transaldolase. Sedoheptulose 7-phosphate can be increased in the blood of patients affected with a transaldolase deficiency (TALDO1; EC 2.2.1.2). (PMID 12881455) Sedoheptulose is a ketoheptose, a monosaccharide with seven carbon atoms and a ketone functional group. It is one of the few heptoses found in nature. (wikipedia).


D-erythrose 4-phosphate

D-Erythrose 4-phosphate is a phosphorylated derivative of erythrose that serves as an important intermediate in the pentose phosphate pathway. It is also used in phenylalanine, tyrosine and tryptophan biosynthesis, and it plays a role in vitamin B6 metabolism (KEGG).


2-deoxy-D-ribose 5-phosphate

Deoxyribose 5-phosphate is a a metabolite in the pentose phosphate pathway. It can be generated from D-glyceraldehdye-3 phosphate via the enzyme 2-Deoxyribose 5-phosphate aldolase (DERA). Alternately Deoxyribose 5-phosphate can be converted to D-glyceraldehyde-3 phosphate that can then feed into the pentose phosphate pathway. Deoxyribose 5-phosphate can also be generated from 2-Deoxy-D-ribose via the enzyme Ribokinase (EC 2.7.1.15). It has been shown in a number of organisms that deoxynucleosides or deoxyriboses cause the induction of aldolases (such as DERA) involved in their catabolism, leading to the utilisation of the pentose moiety as carbon and energy source.


A9Z1X1_HUMAN 6-phosphogluconate dehydrogenase, decarboxylating (trembl)


L-Homoserine

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).


Sarcosine

Sarcosine is the N-methyl derivative of glycine. Sarcosine is metabolized to glycine by the enzyme sarcosine dehydrogenase, while glycine-N-methyl transferase generates sarcosine from glycine. Sarcosine is a natural amino acid found in muscles and other body tissues. In the laboratory it may be synthesized from chloroacetic acid and methylamine. Sarcosine is naturally found in the metabolism of choline to glycine. Sarcosine is sweet to the taste and dissolves in water. It is used in manufacturing biodegradable surfactants and toothpastes as well as in other applications. Sarcosine is ubiquitous in biological materials and is present in such foods as egg yolks, turkey, ham, vegetables, legumes, etc. Sarcosine is formed from dietary intake of choline and from the metabolism of methionine, and is rapidly degraded to glycine. Sarcosine has no known toxicity, as evidenced by the lack of phenotypic manifestations of sarcosinemia, an inborn error of sarcosine metabolism. Sarcosinemia can result from severe folate deficiency because of the folate requirement for the conversion of sarcosine to glycine (Wikipedia). Sarcosine has recently been identified as a biomarker for invasive prostate cancer. It was found to be greatly increased during prostate cancer progression to metastasis and could be detected in urine. Sarcosine levels were also increased in invasive prostate cancer cell lines relative to benign prostate epithelial cells.(PMID: 19212411).

(methylamino)acetate
(methylamino)acetic acid
(methylamino)ethanoate
(methylamino)ethanoic acid
(methylamino)-acetate
(methylamino)-acetic acid
Methylglycine
N-methyl-glycine
N-methylaminoacetate
N-methylaminoacetic acid
N-methylglycine
Sarcosin
Sarcosinate
Sarcosine
Sarcosinic acid
Megly
Methylaminoacetic acid
Sar
2-(methylamino)acetate
Methylaminoacetate


5-Methylthioribose 1-phosphate is an intermediate in methionine biosynthesis. It is converted from 5'-Deoxy-5'-methylthioadenosine by 5'-Deoxy-5'-methylthioadenosine phosphorylase. Then it is converted to methionine (PMID 2153115). In the methionine salvage pathway 5-methylthioribose 1-phosphate isomerase (M1Pi) catalyzes the conversion of 5-methylthioribose 1-phosphate (MTR-1-P) to 5-methylthioribulose 1-phosphate (MTRu-1-P).