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Chorismate
Chorismic acid, more commonly known as its anionic form chorismate, is an important biochemical intermediate in plants and microorganisms. It is a precursor for: * The aromatic amino acids phenylalanine, tryptophan, and tyrosine * Indole, indole derivatives and tryptophan * 2,3-Dihydroxybenzoic acid (DHB) used for enterobactin biosynthesis * The plant hormone salicylic acid * Many alkaloids and other aromatic metabolites. *The folate precursor ''para''-aminobenzoate (pABA) * The biosynthesis of Vitamin K and folate in plants and microorganisms. The name chorismic acid derives from a classical Greek word meaning "to separate", because the compound plays a role as a branch-point in aromatic amino acid biosynthesis.{{Cite journal , last1 = Gibson , first1 = F. , title = The elusive branch-point compound of aromatic amino acid biosynthesis , doi = 10.1016/S0968-0004(98)01330-9 , journal = Trends in Biochemical Sciences , volume = 24 , issue = 1 , pages = 36–38 , year = 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aminodeoxychorismate Synthase
In enzymology, an aminodeoxychorismate synthaseEC 2.6.1.85 is an enzyme that catalyzes the chemical reaction :chorismate + L-glutamine \rightleftharpoons 4-amino-4-deoxychorismate + L-glutamate Thus, the two substrates of this enzyme are chorismate and L-glutamine, whereas its two products are 4-amino-4-deoxychorismate and L-glutamate. It is part of a pathway for the biosynthesis of ''para''-aminobenzoic acid (PABA); a precursor for the production of folates. Folates are family of cofactors that are essential for living organisms. Folate cofactors are used in several one-carbon transfer reactions required during the synthesis of essential metabolites, including methionine and thymidylate. Aminodeoxychorismate synthase (PabB), a 51 kDa protein in ''E. coli'', is encoded by the gene ''pabB''. 4-amino-4-deoxychorismate, the product of PabB, can be converted to ''para''-aminobenzoic acid by the enzyme 4-amino-4-deoxychorismate lyase (PabC). Nonmenclature This enzyme belongs t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorismate Synthase
The enzyme chorismate synthase (EC 4.2.3.5) catalyzes the chemical reaction :5-''O''-(1-carboxyvinyl)-3-phosphoshikimate \rightleftharpoons chorismate + phosphate This enzyme belongs to the family of lyases, specifically those carbon-oxygen lyases acting on phosphates. The systematic name of this enzyme class is 5-''O''-(1-carboxyvinyl)-3-phosphoshikimate phosphate-lyase (chorismate-forming). This enzyme is also called 5-''O''-(1-carboxyvinyl)-3-phosphoshikimate phosphate-lyase. This enzyme participates in phenylalanine, tyrosine and tryptophan biosynthesis. Chorismate synthase catalyzes the last of the seven steps in the shikimate pathway which is used in prokaryotes, fungi and plants for the biosynthesis of aromatic amino acids. It catalyzes the 1,4-trans elimination of the phosphate group from 5-enolpyruvylshikimate-3-phosphate (EPSP) to form chorismate which can then be used in phenylalanine, tyrosine or tryptophan biosynthesis. Chorismate synthase requires the presenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorismate Lyase
The enzyme chorismate lyase () catalyzes the chemical reaction :chorismate \rightleftharpoons 4-hydroxybenzoate + pyruvate : : : : : : This enzyme belongs to the family of lyases, specifically the oxo-acid-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is chorismate pyruvate-lyase (4-hydroxybenzoate-forming). Other names in common use include CL, CPL, and UbiC. This enzyme catalyses the first step in ubiquinone biosynthesis, the removal of pyruvate from chorismate, to yield 4-hydroxybenzoate in ''Escherichia coli'' and other Gram-negative bacteria. Its activity does not require metal cofactors. Activity Catalytic activity * Chorismate = 4HB + pyruvate * This enzyme has an optimum pH at 7.5 Enzymatic activity Inhibited by: * Vanillate * 4-hydroxybenzaldehyde * 3-carboxylmethylaminmethyl-4-hydroxybenzoic acid * 4HB - ubiC is inhibited by the product of the reaction, which scientists believe serves as a control mechanism for the path ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aminodeoxychorismate Lyase
4-amino-4-deoxychorismate lyase () is an enzyme that participates in folate biosynthesis by catalyzing the production of PABA by the following reaction :4-amino-4-deoxychorismate \rightleftharpoons 4-aminobenzoate + pyruvate This enzyme belongs to the family of lyases, specifically the oxo-acid-lyases, which cleave carbon-carbon bonds. This enzyme, encoded by the ''pabC'' gene in bacteria and plants, is also known as PabC or ADC lyase. The fungal enzyme has been designated ABZ2. All known examples of 4-amino-4-deoxychorismate lyase bind PLP (pyridoxal-5'-phosphate Pyridoxal phosphate (PLP, pyridoxal 5'-phosphate, P5P), the active form of vitamin B6, is a coenzyme in a variety of enzymatic reactions. The International Union of Biochemistry and Molecular Biology has catalogued more than 140 PLP-dependent ...), a cofactor employed during catalysis. References * * *Link to article.* * * EC 4.1.3 {{4.1-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorismate Pathway 1
Chorismic acid, more commonly known as its anionic form chorismate, is an important biochemical intermediate in plants and microorganisms. It is a precursor for: * The aromatic amino acids phenylalanine, tryptophan, and tyrosine * Indole, indole derivatives and tryptophan * 2,3-Dihydroxybenzoic acid (DHB) used for enterobactin biosynthesis * The plant hormone salicylic acid * Many alkaloids and other aromatic metabolites. *The folate precursor ''para''-aminobenzoate (pABA) * The biosynthesis of Vitamin K and folate in plants and microorganisms. The name chorismic acid derives from a classical Greek word meaning "to separate", because the compound plays a role as a branch-point in aromatic amino acid biosynthesis.{{Cite journal , last1 = Gibson , first1 = F. , title = The elusive branch-point compound of aromatic amino acid biosynthesis , doi = 10.1016/S0968-0004(98)01330-9 , journal = Trends in Biochemical Sciences , volume = 24 , issue = 1 , pages = 36–38 , year = 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorismate Pathway 2
Chorismic acid, more commonly known as its anionic form chorismate, is an important biochemical intermediate in plants and microorganisms. It is a precursor for: * The aromatic amino acids phenylalanine, tryptophan, and tyrosine * Indole, indole derivatives and tryptophan * 2,3-Dihydroxybenzoic acid (DHB) used for enterobactin biosynthesis * The plant hormone salicylic acid * Many alkaloids and other aromatic metabolites. *The folate precursor ''para''-aminobenzoate (pABA) * The biosynthesis of Vitamin K and folate in plants and microorganisms. The name chorismic acid derives from a classical Greek word meaning "to separate", because the compound plays a role as a branch-point in aromatic amino acid biosynthesis.{{Cite journal , last1 = Gibson , first1 = F. , title = The elusive branch-point compound of aromatic amino acid biosynthesis , doi = 10.1016/S0968-0004(98)01330-9 , journal = Trends in Biochemical Sciences , volume = 24 , issue = 1 , pages = 36–38 , year = 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shikimic Acid
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'' (, the Japanese star anise, ''Illicium anisatum''), from which it was first isolated in 1885 by Johan Fredrik Eykman. The elucidation of its structure was made nearly 50 years later. Biosynthesis Phosphoenolpyruvate and erythrose-4-phosphate condense to form 3-deoxy-D-arabinoheptulosonate-7-phosphate (DAHP), in a reaction catalyzed by the enzyme DAHP synthase. DAHP is then transformed to 3-dehydroquinate (DHQ), in a reaction catalyzed by DHQ synthase. Although this reaction requires nicotinamide adenine dinucleotide (NAD) as a cofactor, the enzymic mechanism regenerates it, resulting in the net use of no NAD. : DHQ is dehydrated to 3-dehydroshikimic acid by the enzyme 3-dehydroquinate dehydratase, which is reduced to shiki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4-Aminobenzoic Acid
4-Aminobenzoic acid (also known as ''para''-aminobenzoic acid or PABA because the two functional groups are attached to the benzene ring across from one another in the ''para'' position) is an organic compound with the formula H2NC6H4CO2H. PABA is a white solid, although commercial samples can appear gray. It is slightly soluble in water. It consists of a benzene ring substituted with amino and carboxyl groups. The compound occurs extensively in the natural world. Production and occurrence In industry, PABA is prepared mainly by two routes: * Reduction of 4-nitrobenzoic acid * Hoffman degradation of the monoamide derived from terephthalic acid. Food sources of PABA include liver, brewer's yeast (and unfiltered beer), kidney, molasses, mushrooms, and whole grains. A review on this compound. Biology Biochemistry PABA is an intermediate in the synthesis of folate by bacteria, plants, and fungi. Many bacteria, including those found in the human intestinal tract such as ''E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5-O-(1-carboxyvinyl)-3-phosphoshikimate
5-enolpyruvylshikimate-3-phosphate (EPSP) synthase is an enzyme produced by plants and microorganisms. EPSPS catalyzes the chemical reaction: : phosphoenolpyruvate (PEP) + 3-phospho shikimate (S3P) phosphate + 5-enolpyruvylshikimate-3-phosphate (EPSP) Thus, the two substrates of this enzyme are phosphoenolpyruvate (PEP) and 3-phosphoshikimate, whereas its two products are phosphate and 5-enolpyruvylshikimate-3-phosphate. This enzyme is not present in animals. It presents an attractive biological target for herbicides, such as glyphosate. A glyphosate-resistant version of this gene has been used in genetically modified crops. Nomenclature The enzyme belongs to the family of transferases, to be specific those transferring aryl or alkyl groups other than methyl groups. The systematic name of this enzyme class is phosphoenolpyruvate:3-phosphoshikimate 5-''O''-(1-carboxyvinyl)-transferase. Other names in common use include: * 5-enolpyruvylshikimate-3-phosphate synthase, * 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ubiquinone
Coenzyme Q, also known as ubiquinone and marketed as CoQ10, is a coenzyme family that is ubiquitous in animals and most bacteria (hence the name ubiquinone). In humans, the most common form is coenzyme Q10 or ubiquinone-10. It is a 1,4-benzoquinone, where Q refers to the quinone chemical group and 10 refers to the number of isoprenyl chemical subunits in its tail. In natural ubiquinones, the number can be anywhere from 6 to 10. This family of fat-soluble substances, which resemble vitamins, is present in all respiring eukaryotic cells, primarily in the mitochondria. It is a component of the electron transport chain and participates in aerobic cellular respiration, which generates energy in the form of ATP. Ninety-five percent of the human body's energy is generated this way. Organs with the highest energy requirements—such as the heart, liver, and kidney—have the highest CoQ10 concentrations. There are three redox states of CoQ: fully oxidized (ubiquinone), semiquinone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4-hydroxybenzoate
4-Hydroxybenzoic acid, also known as ''p''-hydroxybenzoic acid (PHBA), is a monohydroxybenzoic acid, a phenolic derivative of benzoic acid. It is a white crystalline solid that is slightly soluble in water and chloroform but more soluble in polar organic solvents such as alcohols and acetone. 4-Hydroxybenzoic acid is primarily known as the basis for the preparation of its esters, known as parabens, which are used as preservatives in cosmetics and some ophthalmic solutions. It is isomeric with 2-hydroxybenzoic acid, known as salicylic acid, a precursor to aspirin, and with 3-hydroxybenzoic acid. Natural occurrences It is found in plants of the genus ''Vitex'' such as '' V. agnus-castus'' or '' V. negundo'', and in ''Hypericum perforatum'' (St John's wort). It is also found in ''Spongiochloris spongiosa'', a freshwater green alga. The compound is also found in ''Ganoderma lucidum'', a medicinal mushroom with the longest record of use. ''Cryptanaerobacter phenolicus'' is a bact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Hormone
Plant hormone (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, from embryogenesis, the regulation of organ size, pathogen defense, stress tolerance and through to reproductive development. Unlike in animals (in which hormone production is restricted to specialized glands) each plant cell is capable of producing hormones. Went and Thimann coined the term "phytohormone" and used it in the title of their 1937 book. Phytohormones occur across the plant kingdom, and even in algae, where they have similar functions to those seen in higher plants. Some phytohormones also occur in microorganisms, such as unicellular fungi and bacteria, however in these cases they do not play a hormonal role and can better be regarded as secondary metabolites. Characteristics The word hormone is derived from Greek, meaning ''set in motion''. Plant hormones affect gene ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
