|
Erythrose 4-phosphate
Erythrose 4-phosphate is a phosphate of the simple sugar erythrose. It is an intermediate in the pentose phosphate pathway and the Calvin cycle. The enzyme transaldolase catalyzes the formation of erythrose 4-phosphate and fructose 6-phosphate from sedoheptulose 7-phosphate and glyceraldehyde 3-phosphate. This reaction is a part of the non-oxidative phase of the pentose phosphate pathway. In the Calvin cycle, the enzyme fructose-bisphosphate aldolase catalyzes the formation of sedoheptulose 1,7-bisphosphate from erythrose 4-phosphate and dihydroxyacetone phosphate. In addition, it serves as a precursor in the biosynthesis of the aromatic amino acids tyrosine, phenylalanine, and tryptophan. It is used in the first step of the shikimate pathway. At this stage, phosphoenolpyruvate and erythrose-4-phosphate react to form 3-deoxy-D-arabinoheptulosonate-7-phosphate (DAHP), in a reaction catalyzed by the enzyme DAHP synthase. : It also used in 3-hydroxy-1-aminoacetone phosphat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphate
Phosphates are the naturally occurring form of the element phosphorus. In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid, phosphoric acid . The phosphate or orthophosphate ion is derived from phosphoric acid by the removal of three protons . Removal of one proton gives the dihydrogen phosphate ion while removal of two protons gives the hydrogen phosphate ion . These names are also used for salts of those anions, such as ammonium dihydrogen phosphate and trisodium phosphate. File:3-phosphoric-acid-3D-balls.png, Phosphoricacid File:2-dihydrogenphosphate-3D-balls.png, Dihydrogenphosphate File:1-hydrogenphosphate-3D-balls.png, Hydrogenphosphate File:0-phosphate-3D-balls.png, Phosphate or orthophosphate In organic chemistry, phosphate or orthophosphate is an organophosphate, an ester of orthophosphoric acid of the form where one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shikimate Pathway
The shikimate pathway (shikimic acid 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 (tryptophan, phenylalanine, and tyrosine). This pathway is not found in mammals. The five enzymes involved in the shikimate pathway are 3-dehydroquinate dehydratase, shikimate dehydrogenase, shikimate kinase, EPSP synthase, and chorismate synthase. In bacteria and eurkaryotes, the pathway starts with two substrates, phosphoenol pyruvate and erythrose-4-phosphate, are processed by DAHP synthase and 3-dehydroquinate synthase to form 3-dehydroquinate. In archaea, 2-amino-3,7-dideoxy-D-threo-hept-6-ulosonate synthase condenses L-Aspartic-4-semialdehyde with a sugar to form 2-amino-3,7-dideoxy-D-threo-hept-6-ulosonate, which is then turned by 3-dehydroquinate synthase II into 3-dehydroquinate. Both pathways end with chorismate (chrorismic acid), a substrate for the thre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monosaccharide Derivatives
Monosaccharides (from Greek ''monos'': single, '' sacchar'': sugar), also called simple sugars, are the simplest forms of sugar and the most basic units (monomers) from which all carbohydrates are built. Chemically, monosaccharides are polyhydroxy aldehydes with the formula or polyhydroxy ketones with the formula with three or more carbon atoms. They are usually colorless, water-soluble, and crystalline organic solids. Contrary to their name (sugars), only some monosaccharides have a sweet taste. Most monosaccharides have the formula (CH2O)''x'' (though not all molecules with this formula are monosaccharides). Examples of monosaccharides include glucose (dextrose), fructose (levulose), and galactose. Monosaccharides are the building blocks of disaccharides (such as sucrose, lactose and maltose) and polysaccharides (such as cellulose and starch). The table sugar used in everyday vernacular is itself a disaccharide sucrose comprising one molecule of each of the two monosacch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erythrose-4-phosphate Dehydrogenase
Erythrose 4-phosphate is a phosphate of the simple sugar erythrose. It is an intermediate in the pentose phosphate pathway and the Calvin cycle. The enzyme transaldolase catalyzes the formation of erythrose 4-phosphate and fructose 6-phosphate from sedoheptulose 7-phosphate and glyceraldehyde 3-phosphate. This reaction is a part of the non-oxidative phase of the pentose phosphate pathway. In the Calvin cycle, the enzyme fructose-bisphosphate aldolase catalyzes the formation of sedoheptulose 1,7-bisphosphate from erythrose 4-phosphate and dihydroxyacetone phosphate. In addition, it serves as a precursor in the biosynthesis of the aromatic amino acids tyrosine, phenylalanine, and tryptophan. It is used in the first step of the shikimate pathway. At this stage, phosphoenolpyruvate and erythrose-4-phosphate react to form 3-deoxy-D-arabinoheptulosonate-7-phosphate (DAHP), in a reaction catalyzed by the enzyme DAHP synthase. : It also used in 3-hydroxy-1-aminoacetone phosphate biosy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridoxal 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 activities, corresponding to ~4% of all classified activities. The versatility of PLP arises from its ability to covalently bind the substrate, and then to act as an electrophilic catalyst, thereby stabilizing different types of carbanionic reaction intermediates. Role as a coenzyme PLP acts as a coenzyme in all transamination reactions, and in certain decarboxylation, deamination, and racemization reactions of amino acids. The aldehyde group of PLP forms a Schiff-base linkage (internal aldimine) with the ε-amino group of a specific lysine group of the aminotransferase enzyme. The α-amino group of the amino acid substrate displaces the ε-amino group of the active-site lysine residue in a process known as transaldimination. The r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin B6
Vitamin B6 is one of the B vitamins, and is an essential nutrient for humans. The term essential nutrient refers to a group of six chemically similar compounds, i.e., "vitamers", which can be interconverted in biological systems. Its active form, pyridoxal phosphate, pyridoxal 5′-phosphate, serves as a coenzyme in more than 140 enzyme reactions in amino acid, glucose, and lipid metabolism. Plants synthesize pyridoxine as a means of protection from the UV-B, UV-B radiation found in sunlight and for the role it plays in the synthesis of chlorophyll. Animals cannot synthesize any of the various forms of the vitamin, and hence must obtain it via diet, either of plants, or of other animals. There is some absorption of the vitamin produced by intestinal bacteria, but this is not sufficient to meet dietary needs. For adult humans, recommendations from various countries' food regulatory agencies are in the range of 1.0 to 2.0 milligrams (mg) per day. These same agencies also recogni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DAHP Synthase Reaction , an intermediate in the biosynthesis of shikimic acid
{{disambiguation ...
DAHP may refer to: * Washington State Department of Archaeology and Historic Preservation, an independent government agency in Washington state * 3-deoxy-D-arabinoheptulosonate-7-phosphate 3-Deoxy--''arabino''-heptulosonic acid 7-phosphate (DAHP) is a 7-carbon ulosonic acid. This compound is found in the Shikimic acid pathway, shikimic acid biosynthesis pathway and is an intermediate in the amino acid synthesis, production of aroma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DAHP Synthase
3-Deoxy-D-arabinoheptulosonate 7-phosphate (DAHP) synthase () is the first enzyme in a series of metabolic Chemical reaction, reactions known as the shikimate pathway, which is responsible for the biosynthesis of the amino acids phenylalanine, tyrosine, and tryptophan. Since it is the first enzyme in the shikimate pathway, it controls the amount of carbon entering the pathway. Enzyme enzyme inhibitor, inhibition is the primary method of regulating the amount of carbon entering the pathway. Forms of this enzyme differ between organisms, but can be considered DAHP synthase based upon the reaction that is catalyzed by this enzyme. In enzymology, a DAHP synthase () is an enzyme that catalysis, catalyzes the chemical reaction :phosphoenolpyruvate + D-erythrose 4-phosphate + H2O \rightleftharpoons 3-deoxy-D-arabino-hept-2-ulosonate 7-phosphate + phosphate The three substrate (biochemistry), substrates of this enzyme are phosphoenolpyruvate, D-erythrose 4-phosphate, and water, H2O, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-deoxy-D-arabinoheptulosonate-7-phosphate
3-Deoxy--''arabino''-heptulosonic acid 7-phosphate (DAHP) is a 7-carbon ulosonic acid. This compound is found in the Shikimic acid pathway, shikimic acid biosynthesis pathway and is an intermediate in the amino acid synthesis, production of aromatic amino acids. Phosphoenolpyruvate and erythrose-4-phosphate react to form 3-deoxy--''arabino''-heptulosonate-7-phosphate (DAHP), in a reaction catalyzed by the enzyme DAHP synthase. : DAHP is then transformed to 3-Dehydroquinic acid, 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. : The mechanism of ring closure is complex, but involves an aldol condensation at C-2 and C-7. Metabolic engineering has improved production of DAHP by ''Escherichia coli''. The first step, condensation of 3-deoxy--''arabino''-heptulosonic acid 7-phosphate (DAHP) from PEP/E4P, use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphoenolpyruvate
Phosphoenolpyruvate (2-phosphoenolpyruvate, PEP) is the carboxylic acid derived from the enol of pyruvate and a phosphate anion. It exists as an anion. PEP is an important intermediate in biochemistry. It has the high-energy phosphate, highest-energy phosphate bond found (−61.9 kJ/mol) in organisms, and is involved in glycolysis and gluconeogenesis. In plants, it is also involved in the biosynthesis of various aromatic compounds, and in carbon fixation; in bacteria, it is also used as the source of energy for the phosphotransferase system. In glycolysis PEP is formed by the action of the enzyme enolase on 2-phosphoglyceric acid. Metabolism of PEP to pyruvic acid by pyruvate kinase (PK) generates adenosine triphosphate (ATP) via substrate-level phosphorylation. ATP is one of the major currencies of chemical energy within Cell (biology), cells. In gluconeogenesis PEP is formed from the decarboxylation of oxaloacetate and hydrolysis of one guanosine triphosphate molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
