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Pantothenic acid, also called vitamin B5, is a water-soluble vitamin required to sustain life. Pantothenic acid is needed to form coenzyme-A (CoA), and is thus critical in the metabolism and synthesis of carbohydrates, proteins, and fats. Its name is derived from the Greek pantothen meaning "from everywhere" and small quantities of pantothenic acid are found in nearly every food, with high amounts in whole grain cereals, legumes, eggs, meat, and royal jelly. Pantothenic acid is classified as a member of the secondary alcohols. Secondary alcohols are compounds containing a secondary alcohol functional group, with the general structure HOC(R)(R') (R,R'=alkyl, aryl). Pantothenic acid is considered to be soluble (in water) and acidic.

Creatinine, or creatine anhydride, is a breakdown product of creatine phosphate in muscle. The loss of a water molecule from creatine results in the formation of creatinine. Creatinine is transferred to the kidneys by blood plasma, whereupon it is eliminated from the body by glomerular filtration and partial tubular excretion. Creatinine is usually produced at a fairly constant rate by the body. Measuring serum creatinine is a simple test and it is the most commonly used indicator of renal function. A rise in blood creatinine levels is observed only with marked damage to functioning nephrons. Therefore, this test is not suitable for detecting early kidney disease. The typical reference range for women is considered about 45-90 µmol/L; for men 60-110 µmol/L. Creatine and creatinine are metabolized in the kidneys, muscle, liver, and pancreas.

Xanthosine, also known as xanthine riboside, belongs to the class of organic compounds known as purine nucleosides. Purine nucleosides are compounds comprising a purine base attached to a ribosyl or deoxyribosyl moiety. Xanthosine is a nucleoside derived from xanthine and ribose. Xanthosine exists in all living species, ranging from bacteria to plants to humans. In plants xanthosine is the biosynthetic precursor to 7-methylxanthosine which is produced by the action of the enzyme known as 7-methylxanthosine synthase. 7-Methylxanthosine in turn is the precursor to theobromine (the active alkaloid in chocolate), which in turn is the precursor to caffeine, the active alkaloid in coffee and tea. Within humans, xanthosine participates in a number of enzymatic reactions. In particular, xanthosine can be biosynthesized from xanthylic acid; which is catalyzed by the enzyme cytosolic purine 5'-nucleotidase. In addition, xanthosine can be converted into xanthine and ribose 1-phosphate; which is mediated by the enzyme purine nucleoside phosphorylase. Xanthosine monophosphate (XMP) is an intermediate in purine metabolism, formed from IMP (inosine monophosphate).

Pantothenic acid is a member of the class of pantothenic acids that is an amide formed from pantoic acid and beta-alanine. It has a role as a plant metabolite. It is a conjugate acid of a pantothenate. DL-Pantothenic acid is a natural product found in Daphnia pulex, Drosophila melanogaster, and other organisms with data available.

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.

Cinnamic acid, also known as (Z)-cinnamate or 3-phenyl-acrylate, belongs to the class of organic compounds known as cinnamic acids. These are organic aromatic compounds containing a benzene and a carboxylic acid group forming 3-phenylprop-2-enoic acid. Cinnamic acid can be obtained from oil of cinnamon, or from balsams such as storax. Cinnamic acid is a weakly acidic compound (based on its pKa). It is a white crystalline compound that is slightly soluble in water, and freely soluble in many organic solvents. Cinnamic acid exists in all living organisms, ranging from bacteria to plants to humans. Outside of the human body, cinnamic acid has been detected, but not quantified in, chinese cinnamons. In plants, cinnamic acid is a central intermediate in the biosynthesis of myriad natural products include lignols (precursors to lignin and lignocellulose), flavonoids, isoflavonoids, coumarins, aurones, stilbenes, catechin, and phenylpropanoids.

Isovalerylalanine, also known as isopentanoylalanine, belongs to the class of organic compounds known as N-acyl-L-alpha-amino acids. These are N-acylated alpha amino acids which have the L-configuration of the alpha-carbon atom. Isovalerylalanine results from the formal condensation of the carboxy group of isovaleric acid with the amino group of L-alanine. Isovalerylalanine is one of the constituents of the organic acid profile in isovaleric acidemia, it is believed to be formed by the action of the enzyme glycine N-acylase on alanine, using isovaleryl-CoA as a substrate (PMID: 6197208). Isovaleric acidemia was the first organic acid acidemia to be documented in humans. It is an autosomal recessive inborn error in the metabolism of leucine, caused by a deficiency of the mitochondrial enzyme isovaleryl-CoA dehydrogenase (IVD) that results in the accumulation isovaleryl-CoA derivatives (PMID: 16602101). The excess of isovaleryl-CoA in plasma allows for the formation of condensation derivatives, such as isovalerylalanine which makes it one of the biomarkers for this condition.

The 7,8-dihydro-7,8-dihydroxy derivative of kynurenic acid." []

Glycyl-Isoleucine is a dipeptide composed of glycine and isoleucine. It is an incomplete breakdown product of protein digestion or protein catabolism. Some dipeptides are known to have physiological or cell-signaling effects although most are simply short-lived intermediates on their way to specific amino acid degradation pathways following further proteolysis. This dipeptide has not yet been identified in human tissues or biofluids and so it is classified as an 'Expected' metabolite.

N-alpha-Acetyl-L-lysine also known as Nalpha-Acetyllysine, belongs to the class of organic compounds known as N-acyl-alpha amino acids. N-acyl-alpha amino acids are compounds containing an alpha amino acid which bears an acyl group at its terminal nitrogen atom. N-alpha-Acetyl-L-lysine can also be classified as an alpha amino acid or a derivatized alpha amino acid. Technically, N-alpha-Acetyl-L-lysine is a biologically available N-terminal capped form of the proteinogenic alpha amino acid L-lysine. Unlike L-lysine, acetylated lysine derivatives such as N-alpha-Acetyl-L-lysine are zwitterionic compounds. These are molecules that contains an equal number of positively- and negatively-charged functional groups. N-alpha-Acetyl-L-lysine is found naturally in eukaryotes ranging from yeast to plants to humans. N-acetyl amino acids can be produced either via direct synthesis of specific N-acetyltransferases or via the proteolytic degradation of N-acetylated proteins by specific hydrolases. N-terminal acetylation of proteins is a widespread and highly conserved process in eukaryotes that is involved in protection and stability of proteins (PMID: 16465618). About 85% of all human proteins and 68% of all yeast proteins are acetylated at their N-terminus (PMID: 21750686). Several proteins from prokaryotes and archaea are also modified by N-terminal acetylation. The majority of eukaryotic N-terminal-acetylation reactions occur through N-acetyltransferase enzymes or NAT’s (PMID: 30054468). These enzymes consist of three main oligomeric complexes NatA, NatB, and NatC, which are composed of at least a unique catalytic subunit and one unique ribosomal anchor. The substrate specificities of different NAT enzymes are mainly determined by the identities of the first two N-terminal residues of the target protein. The human NatA complex co-translationally acetylates N-termini that bear a small amino acid (A, S, T, C, and occasionally V and G) (PMID: 30054468). NatA also exists in a monomeric state and can post-translationally acetylate acidic N-termini residues (D-, E-). NatB and NatC acetylate N-terminal methionine with further specificity determined by the identity of the second amino acid. N-acetylated amino acids, such as N-alpha-Acetyl-L-lysine can be released by an N-acylpeptide hydrolase from peptides generated by proteolytic degradation (PMID: 16465618). In addition to the NAT enzymes and protein-based acetylation, N-acetylation of free lysine can also occur. In particular, N-alpha-Acetyl-L-lysine can be biosynthesized from L-lysine and acetyl-CoA via the enzyme known as Lysine N-acetyltransferase. Individuals with hyperlysinaemia due to L-lysine alpha-ketoglutarate reductase deficiency will excrete high levels of N-alpha-Acetyl-L-lysine in their urine (PMID: 116084). L-lysine alpha-ketoglutarate reductase deficiency, if untreated, can lead to neurological and behavioral deficits (PMID: 116084). Many N-acetylamino acids are classified as uremic toxins if present in high abundance in the serum or plasma (PMID: 26317986; PMID: 20613759). Uremic toxins are a diverse group of endogenously produced molecules that, if not properly cleared or eliminated by the kidneys, can cause kidney damage, cardiovascular disease and neurological deficits (PMID: 18287557).

Cinnamic acid is a monocarboxylic acid that consists of acrylic acid bearing a phenyl substituent at the 3-position. It is found in Cinnamomum cassia. It has a role as a plant metabolite. It is a member of styrenes and a member of cinnamic acids. It is a conjugate acid of a cinnamate. trans-Cinnamic acid is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Cinnamic acid is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Cinnamic acid is a natural product found in Ipomoea leptophylla, Camellia sinensis, and other organisms with data available. Cinnamic acid has the formula C6H5CHCHCOOH and is an odorless white crystalline acid, which is slightly soluble in water. It has a melting point of 133 degree centigrade and a boiling point of 300 degree centigrade. Cinnamic acid is a metabolite found in or produced by Saccharomyces cerevisiae. See also: Cinnamon (part of); Chinese Cinnamon (part of); Stevia rebaudiuna Leaf (part of) ... View More ...

A hydroxy-1,4-naphthoquinone that is 1,4-naphthoquinone substituted by hydroxy and 3-methylbut-2-en-1-yl groups at positions 2 and 3, respectively. It is a natural compound that exhibits antibacterial and anticancer properties, first isolated in 1882 from the bark of Tabebuia avellanedae." []

A benzochromenone that is 3,4-dihydro-2H-benzo[h]chromene-5,6-dione substituted by geminal methyl groups at position 2. Isolated from Tabebuia avellanedae, it exhibits antineoplastic and anti-inflammatory activities." []

3-methoxy-4',5-dihydroxy-trans-stilbene is a stilbenoid that is trans-resveratrol in which one of the meta-hydroxy groups is converted to the corresponding methyl ether. It is functionally related to a trans-resveratrol. 3-Methoxy-4',5-dihydroxy-trans-stilbene is a natural product found in Soymida febrifuga, Streptomyces avermitilis, and other organisms with data available.

5-[2-(4-methoxyphenyl)ethenyl]benzene-1,3-diol is a stilbenoid. (E)-5-(4-Methoxystyryl)benzene-1,3-diol has been reported in Alpinia hainanensis, Dracaena cochinchinensis, and other organisms with data available.

N-Acetyl-L-valine or N-Acetylvaline, belongs to the class of organic compounds known as N-acyl-alpha amino acids. N-acyl-alpha amino acids are compounds containing an alpha amino acid which bears an acyl group at its terminal nitrogen atom. N-Acetylvaline can also be classified as an alpha amino acid or a derivatized alpha amino acid. Technically, N-Acetylvaline is a biologically available N-terminal capped form of the proteinogenic alpha amino acid L-valine. N-acetyl amino acids can be produced either via direct synthesis of specific N-acetyltransferases or via the proteolytic degradation of N-acetylated proteins by specific hydrolases. N-terminal acetylation of proteins is a widespread and highly conserved process in eukaryotes that is involved in protection and stability of proteins (PMID: 16465618). About 85% of all human proteins and 68% of all yeast proteins are acetylated at their N-terminus (PMID: 21750686). Several proteins from prokaryotes and archaea are also modified by N-terminal acetylation. The majority of eukaryotic N-terminal-acetylation reactions occur through N-acetyltransferase enzymes or NAT’s (PMID: 30054468). These enzymes consist of three main oligomeric complexes NatA, NatB, and NatC, which are composed of at least a unique catalytic subunit and one unique ribosomal anchor. The substrate specificities of different NAT enzymes are mainly determined by the identities of the first two N-terminal residues of the target protein. The human NatA complex co-translationally acetylates N-termini that bear a small amino acid (A, S, T, C, and occasionally V and G) (PMID: 30054468). NatA also exists in a monomeric state and can post-translationally acetylate acidic N-termini residues (D-, E-). NatB and NatC acetylate N-terminal methionine with further specificity determined by the identity of the second amino acid. N-acetylated amino acids, such as N-acetylvaline can be released by an N-acylpeptide hydrolase from peptides generated by proteolytic degradation (PMID: 16465618). In addition to the NAT enzymes and protein-based acetylation, N-acetylation of free valine can also occur. Excessive amounts N-acetyl amino acids including N-acetylvaline(as well as N-acetylglycine, N-acetylserine, N-acetylmethionine, N-acetylglutamate, N-acetylalanine, N-acetylleucine and smaller amounts of N-acetylglutamine, N-acetylisoleucine, and N-acetylthreonine) can be detected in the urine with individuals with acylase I deficiency, a genetic disorder (PMID: 16465618). Aminoacylase I is a soluble homodimeric zinc binding enzyme that catalyzes the formation of free aliphatic amino acids from N-acetylated precursors. In humans, Aminoacylase I is encoded by the aminoacylase 1 gene (ACY1) on chromosome 3p21 that consists of 15 exons (OMIM 609924). Individuals with aminoacylase I deficiency will experience convulsions, hearing loss and difficulty feeding (PMID: 16465618). ACY1 can also catalyze the reverse reaction, the synthesis of acetylated amino acids. Many N-acetylamino acids, including N-acetylthreonine, are classified as uremic toxins if present in high abundance in the serum or plasma (PMID: 26317986; PMID: 20613759). Uremic toxins are a diverse group of endogenously produced molecules that, if not properly cleared or eliminated by the kidneys, can cause kidney damage, cardiovascular disease and neurological deficits (PMID: 18287557).

Threonylisoleucine is a dipeptide composed of threonine and isoleucine. It is an incomplete breakdown product of protein digestion or protein catabolism. Dipeptides are organic compounds containing a sequence of exactly two alpha-amino acids joined by a peptide bond. Some dipeptides are known to have physiological or cell-signalling effects although most are simply short-lived intermediates on their way to specific amino acid degradation pathways following further proteolysis.

Alanylvaline is a dipeptide composed of alanine and valine. It is an incomplete breakdown product of protein digestion or protein catabolism. Some dipeptides are known to have physiological or cell-signaling effects although most are simply short-lived intermediates on their way to specific amino acid degradation pathways following further proteolysis.

3,4-Dihydro-2H-1-benzopyran-2-one, also known as 3,4-dihydrocoumarin or 1,2-benzodihydropyrone, belongs to the class of organic compounds known as 3,4-dihydrocoumarins. These are 3,4-dihydrogenated coumarins. Coumarin is a bicyclic compound that are 1-benzopyran carrying an oxo group at the 2-position. 3,4-Dihydro-2H-1-benzopyran-2-one exists in all living organisms, ranging from bacteria to humans. 3,4-Dihydro-2H-1-benzopyran-2-one is a sweet, almond, and cinnamon tasting compound. 3,4-Dihydro-2H-1-benzopyran-2-one has been detected, but not quantified, in several different foods, such as green vegetables, pulses, sour cherries, and tarragons. A chromanone that is the 3,4-dihydro derivative of coumarin.

Glutamylproline is a dipeptide composed of glutamate and proline, and is a proteolytic breakdown product of larger proteins. It belongs to the family of N-acyl-alpha amino acids and derivatives. These are compounds containing an alpha amino acid which bears an acyl group at its terminal nitrogen atom. Glutamylproline is an incomplete breakdown product of protein digestion or protein catabolism. Some dipeptides are known to have physiological or cell-signaling effects although most are simply short-lived intermediates on their way to specific amino acid degradation pathways following further proteolysis.

4-Hydroxyphenylpyruvic acid (4-HPPA) is a keto acid that is involved in the tyrosine catabolism pathway. It is a product of the enzyme (R)-4-hydroxyphenyllactate dehydrogenase (EC 1.1.1.222) and is formed during tyrosine metabolism. The conversion from tyrosine to 4-HPPA is catalyzed by tyrosine aminotransferase. Additionally, 4-HPPA can be converted to homogentisic acid which is one of the precursors to ochronotic pigment. The enzyme 4-hydroxyphenylpyruvic acid dioxygenase (HPD) catalyzes the reaction that converts 4-hydroxyphenylpyruvic acid to homogentisic acid. A deficiency in the catalytic activity of HPD is known to lead to tyrosinemia type III, an autosomal recessive disorder characterized by elevated levels of blood tyrosine and massive excretion of tyrosine derivatives into urine. It has been shown that hawkinsinuria, an autosomal dominant disorder characterized by the excretion of 'hawkinsin,' may also be a result of HPD deficiency (PMID: 11073718). Moreover, 4-hydroxyphenylpyruvic acid is also found to be associated in phenylketonuria, which is also an inborn error of metabolism. There are two isomers of HPPA, specifically 4HPPA and 3HPPA, of which 4HPPA is the most common. 4-HPPA has been found to be a microbial metabolite in Escherichia (ECMDB).

Pyrene-1,2-oxide is a member of phenanthrenes.

8-chlorotheophylline is 1,3-Dimethylxanthine in which the hydrogen at position 8 is substituted by chlorine. It has a role as a central nervous system stimulant. It is a member of purines and an organochlorine compound. It is a conjugate acid of an 8-chlorotheophylline(1-). 8-Chlorotheophylline is a stimulant drug of the xanthine chemical class, with physiological effects similar to caffeine. Its main use is in combination with [Diphenhydramine] as the antiemetic drug [Dimenhydrinate]. The stimulant properties of 8-chlorotheophylline are thought to ward off the drowsiness caused by diphenhydramine's anti-histamine activity in the central nervous system. 8-chlorotheophylline produces a number of effects including nervousness, restlessness, insomnia, headache, and nausea, which are primarily attributed to its ability to block the adenosine receptor. Because adenosine causes a decrease in neuronal firing, blockade of the adenosine receptor causes the reverse effect resulting in excitation.