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Pyrophosphatases
Pyrophosphatases, also known as diphosphatases, are acid anhydride hydrolases that act upon diphosphate bonds. Examples include: * Inorganic pyrophosphatase, which acts upon the free pyrophosphate ion * Tobacco acid pyrophosphatase, which catalyses the hydrolysis of a phosphoric ester * Various organic pyrophosphatases, which act upon organic molecules with the pyrophosphate group (but excluding triphosphatases that act on the final bond): ** Thiamine pyrophosphatase In enzymology, a nucleoside-diphosphatase () is an enzyme that catalyzes the chemical reaction :a nucleoside diphosphate + H2O \rightleftharpoons a nucleotide + phosphate Thus, the two substrates of this enzyme are nucleoside diphosphate and ... See also * References External links * EC 3.6.1 {{3.6-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid Anhydride Hydrolases
Acid anhydride hydrolases are a class of hydrolase enzymes that catalyze the hydrolysis of an acid anhydride bond. They are classified under Enzyme Commission number, EC number 3.6. One well known member of this class is GTPase. See also * List of EC numbers (EC 3)#EC 3.6: Act on acid anhydrides References External links * * EC 3.6 {{3.6-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphosphate
In chemistry, pyrophosphates are phosphorus oxyanions that contain two phosphorus atoms in a P–O–P linkage. A number of pyrophosphate salts exist, such as disodium pyrophosphate (Na2H2P2O7) and tetrasodium pyrophosphate (Na4P2O7), among others. Often pyrophosphates are called diphosphates. The parent pyrophosphates are derived from partial or complete neutralization of pyrophosphoric acid. The pyrophosphate bond is also sometimes referred to as a phosphoanhydride bond, a naming convention which emphasizes the loss of water that occurs when two phosphates form a new P–O–P bond, and which mirrors the nomenclature for anhydrides of carboxylic acids. Pyrophosphates are found in ATP and other nucleotide triphosphates, which are important in biochemistry. The term pyrophosphate is also the name of esters formed by the condensation of a phosphorylated biological compound with inorganic phosphate, as for dimethylallyl pyrophosphate. This bond is also referred to as a high-energ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Pyrophosphatase
Inorganic pyrophosphatase (or inorganic diphosphatase, PPase) is an enzyme () that catalyzes the conversion of one ion of pyrophosphate to two phosphate ions. This is a highly exergonic reaction, and therefore can be coupled to unfavorable biochemical transformations in order to drive these transformations to completion. The functionality of this enzyme plays a critical role in lipid metabolism (including lipid synthesis and degradation), calcium absorption and bone formation, and DNA synthesis, as well as other biochemical transformations. Two types of inorganic diphosphatase, very different in terms of both amino acid sequence and structure, have been characterised to date: soluble and transmembrane proton-pumping pyrophosphatases (sPPases and H(+)-PPases, respectively). sPPases are ubiquitous proteins that hydrolyse pyrophosphate to release heat, whereas H+-PPases, so far unidentified in animal and fungal cells, couple the energy of PPi hydrolysis to proton movement across ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tobacco Acid Pyrophosphatase
Tobacco Acid Pyrophosphatase (TAP) is an enzyme that catalyses the hydrolysis of a phosphoric ester bond in a broad spectrum of molecules, including the 5'-end of mRNA In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of Protein biosynthesis, synthesizing a protein. mRNA is .... During mRNA maturation the 5' triphosphate of the new mRNA molecule is rapidly removed. The diphosphate 5' end then attacks the α-phosphorus atom of a methylated GTP to form a very unusual 5'-5' triphosphate linkage, called ''cap''. In molecular biology, TAP is used to hydrolyse a phosphodiester bond of this particular structure and release a mRNA molecule with only one phosphate group in the 5'-end, for instance in protocols for RACE (Rapid Amplification of cDNA Ends). References {{reflist Enzymes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphoric Ester
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. They perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties. '' Nomenclature Etymology The word '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiamine Pyrophosphatase
In enzymology, a nucleoside-diphosphatase () is an enzyme that catalyzes the chemical reaction :a nucleoside diphosphate + H2O \rightleftharpoons a nucleotide + phosphate Thus, the two substrates of this enzyme are nucleoside diphosphate and H2O, whereas its two products are nucleotide and phosphate. This enzyme belongs to the family of hydrolases, specifically those acting on acid anhydrides in phosphorus-containing anhydrides. The systematic name of this enzyme class is nucleoside-diphosphate phosphohydrolase. Other names in common use include thiamine pyrophosphatase, UDPase, inosine diphosphatase, adenosine diphosphatase, IDPase, ADPase, adenosinepyrophosphatase, guanosine diphosphatase, guanosine 5'-diphosphatase, inosine 5'-diphosphatase, uridine diphosphatase, uridine 5'-diphosphatase, nucleoside diphosphate phosphatase, type B nucleoside diphosphatase, GDPase, CDPase, nucleoside 5'-diphosphatase, type L nucleoside diphosphatase, NDPase, and nucleoside diphosphate phos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
