Names | |
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Preferred IUPAC name (1s,4s)-1-(2-Carboxy-2-oxoethyl)-4-hydroxycyclohexa-2,5-diene-1-carboxylic acid | |
Other names Prephenate; cis-1-Carboxy-4-hydroxy-α-oxo-2,5-cyclohexadiene-1-propanoic acid | |
Identifiers | |
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3D model (JSmol) | |
ChEBI | |
ChemSpider | |
MeSH | Prephenic+acid |
PubChem CID |
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UNII |
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CompTox Dashboard (EPA) | |
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Properties | |
C10H10O6 | |
Molar mass | 226.184 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Prephenic acid, commonly also known by its anionic form prephenate, is an intermediate in the biosynthesis of the aromatic amino acids phenylalanine and tyrosine, as well as of a large number of secondary metabolites of the shikimate pathway.
Prephenic acid occurs naturally as an intermediate in the biosynthesis of phenylalanine and tyrosine via the shikimic acid pathway. [1] [2] It is formed from chorismic acid by chorismate mutase. It can be dehydrated by prephenate dehydratase to phenylpyruvic acid, which is a precursor of phenylalanine. Alternatively, it can be dehydrated by prephenate dehydrogenase to 4-hydroxyphenylpyruvic acid, which is a precursor of tyrosine. [1]
It is biosynthesized by a [3,3]-sigmatropic Claisen rearrangement of chorismate. [3] [4]
Prephenic acid is unstable; as a 1,4-cyclohexadiene, it is easily aromatized, for example, under the influence of acids or bases. This instability makes both isolation and synthesis difficult. Prephenic acid was first isolated from mutants of Escherichia coli that were unable to convert prephenic acid to phenylpyruvic acid. During this process, the barium salt was obtained. [2]
Prephenic acid is an example of achiral (optically inactive) molecule which has two pseudoasymmetric atoms (i.e. stereogenic but not chirotopic centers), the C1 and the C4 cyclohexadiene ring atoms. It has been shown [5] that of the two possible diastereoisomers, the natural prephenic acid is one that has both substituents at higher priority (according to CIP rules) on the two pseudoasymmetric carbons, i.e. the carboxyl and the hydroxyl groups, in the cis configuration, or (1s,4s) according to the new IUPAC stereochemistry rules (2013). [6]
The other stereoisomer, i.e. trans or, better, (1r,4r), is called epiprephenic.
L-Tyrosine or tyrosine or 4-hydroxyphenylalanine is one of the 20 standard amino acids that are used by cells to synthesize proteins. It is a non-essential amino acid with a polar side group. The word "tyrosine" is from the Greek tyrós, meaning cheese, as it was first discovered in 1846 by German chemist Justus von Liebig in the protein casein from cheese. It is called tyrosyl when referred to as a functional group or side chain. While tyrosine is generally classified as a hydrophobic amino acid, it is more hydrophilic than phenylalanine. It is encoded by the codons UAC and UAU in messenger RNA.
The Claisen rearrangement is a powerful carbon–carbon bond-forming chemical reaction discovered by Rainer Ludwig Claisen. The heating of an allyl vinyl ether will initiate a [3,3]-sigmatropic rearrangement to give a γ,δ-unsaturated carbonyl, driven by exergonically favored carbonyl CO bond formation (Δ = −327 kcal/mol.
Shikimic acid, more commonly known as its anionic form shikimate, is a cyclohexene, a cyclitol and a cyclohexanecarboxylic acid. It is an important biochemical metabolite in plants and microorganisms. Its name comes from the Japanese flower shikimi, from which it was first isolated in 1885 by Johan Fredrik Eykman. The elucidation of its structure was made nearly 50 years later.
Chorismic acid, more commonly known as its anionic form chorismate, is an important biochemical intermediate in plants and microorganisms. It is a precursor for:
In organic chemistry an enol ether is an alkene with an alkoxy substituent. The general structure is R2C=CR-OR where R = H, alkyl or aryl. A common subfamily of enol ethers are vinyl ethers, with the formula ROCH=CH2. Important enol ethers include the reagent 3,4-dihydropyran and the monomers methyl vinyl ether and ethyl vinyl ether.
3-Dehydroquinic acid (DHQ) is the first carbocyclic intermediate of the shikimate pathway. It is created from 3-deoxyarabinoheptulosonate 7-phosphate, a 7-carbon ulonic acid, by the enzyme DHQ synthase. The mechanism of ring closure is complex, but involves an aldol condensation at C-2 and C-7.
Cyanidin is a natural organic compound. It is a particular type of anthocyanidin. It is a pigment found in many red berries including grapes, bilberry, blackberry, blueberry, cherry, chokeberry, cranberry, elderberry, hawthorn, loganberry, açai berry and raspberry. It can also be found in other fruits such as apples and plums, and in red cabbage and red onion. It has a characteristic reddish-purple color, though this can change with pH; solutions of the compound are red at pH < 3, violet at pH 7-8, and blue at pH > 11. In certain fruits, the highest concentrations of cyanidin are found in the seeds and skin. Cyanidin has been found to be a potent sirtuin 6 (SIRT6) activator.
Amino acid biosynthesis is the set of biochemical processes by which the amino acids are produced. The substrates for these processes are various compounds in the organism's diet or growth media. Not all organisms are able to synthesize all amino acids. For example, humans can synthesize 11 of the 20 standard amino acids. These 11 are called the non-essential amino acids.
Tryptophan hydroxylase (TPH) is an enzyme (EC 1.14.16.4) involved in the synthesis of the monoamine neurotransmitter serotonin. Tyrosine hydroxylase, phenylalanine hydroxylase, and tryptophan hydroxylase together constitute the family of biopterin-dependent aromatic amino acid hydroxylases. TPH catalyzes the following chemical reaction
Prephenate dehydrogenase is an enzyme found in the shikimate pathway, and helps catalyze the reaction from prephenate to tyrosine.
In enzymology, chorismate mutase is an enzyme that catalyzes the chemical reaction for the conversion of chorismate to prephenate in the pathway to the production of phenylalanine and tyrosine, also known as the shikimate pathway. Hence, this enzyme has one substrate, chorismate, and one product, prephenate. Chorismate mutase is found at a branch point in the pathway. The enzyme channels the substrate, chorismate to the biosynthesis of tyrosine and phenylalanine and away from tryptophan. Its role in maintaining the balance of these aromatic amino acids in the cell is vital. This is the single known example of a naturally occurring enzyme catalyzing a pericyclic reaction. Chorismate mutase is only found in fungi, bacteria, and higher plants. Some varieties of this protein may use the morpheein model of allosteric regulation.
The enzyme 3-dehydroquinate dehydratase (EC 4.2.1.10) catalyzes the chemical reaction
Arogenate dehydratase (ADT) (EC 4.2.1.91) is an enzyme that catalyzes the chemical reaction
The enzyme chorismate synthase catalyzes the chemical reaction
The enzyme prephenate dehydratase (EC 4.2.1.51) catalyzes the chemical reaction
In enzymology, glutamate-prephenate aminotransferase is an enzyme that catalyzes the chemical reaction
Shikimate kinase (EC 2.7.1.71) is an enzyme that catalyzes the ATP-dependent phosphorylation of shikimate to form shikimate 3-phosphate. This reaction is the fifth step of the shikimate pathway, which is used by plants and bacteria to synthesize the common precursor of aromatic amino acids and secondary metabolites. The systematic name of this enzyme class is ATP:shikimate 3-phosphotransferase. Other names in common use include shikimate kinase (phosphorylating), and shikimate kinase II.
Rosavin are a family of cinnamyl mono- and diglycosides that are key ingredients of Rhodiola rosea L.,. R. rosea is an important medicinal plant commonly used throughout Europe, Asia, and North America, that has been recognized as a botanical adaptogen by the European Medicines Agency. Rosavin production is specific to R. rosea and R. sachalinenis, and the biosynthesis of these glycosides occurs spontaneously in Rhodiola roots and rhizomes. The production of rosavins increases in plants as they get older, and the amount of the cinnamyl alcohol glycosides depends on the place of origin of the plant.
The shikimate pathway is a seven-step metabolic pathway used by bacteria, archaea, fungi, algae, some protozoans, and plants for the biosynthesis of folates and aromatic amino acids. This pathway is not found in mammals.
Arogenic acid is an intermediate in the biosynthesis of phenylalanine and tyrosine. At physiological pH it exists as its conjugate base arogenate as the acid form is unstable.
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