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Bisphosphate
Bisphosphate may refer to: *(ribulose-bisphosphate carboxylase)-lysine N-methyltransferase (EC 2.1.1.127), an enzyme that catalyzes the chemical reaction S-adenosyl-L-methionine + ibulose-1,5-bisphosphate carboxylaselysine S-adenosyl-L-homocysteine + ibulose-1,5-bisphosphate carboxylaseN6-methyl-L-lysine *3'(2'),5'-bisphosphate nucleotidase (EC 3.1.3.7), an enzyme that catalyzes the chemical reaction adenosine 3',5'-bisphosphate + H2O adenosine 5'-phosphate + phosphate * Fructose 1,6-bisphosphate, fructose sugar phosphorylated on carbons 1 and 6 *Fructose 2,6-bisphosphate (or fructose 2,6-diphosphate), abbreviated Fru-2,6-P2, a metabolite which allosterically affects the activity of the enzymes phosphofructokinase 1 (PFK-1) and fructose 1,6-bisphosphatase (FBPase-1) to regulate glycolysis and gluconeogenesis * Fructose-2,6-bisphosphate 2-phosphatase (EC 3.1.3.46), an enzyme that catalyzes the chemical reaction beta-D-fructose 2,6-bisphosphate + H2O D-fructose 6-phosphate + phosphat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucose-1,6-bisphosphate Synthase
Glucose-1,6-bisphosphate synthase is a type of enzyme called a phosphotransferase and is involved in mammalian starch and sucrose metabolism (KEGG2.7.1.106. It catalyzes the transfer of a phosphate group from 1,3-bisphosphoglycerate to glucose-1-phosphate, yielding 3-phosphoglycerate and glucose-1,6-bisphosphate. (image courtesy of the BRENDA enzyme database) The enzyme requires a divalent metal ion cofactor. Zinc (Zn2+), Magnesium (Mg2+), Manganese (Mn2+), Calcium (Ca2+), Nickel (Ni2+), Copper (Cu2+), Cadmium (Cd2+) are all proven effective cofactors ''in vitro''. Additionally, the enzyme appears to function optimally in a pH range from 7.3–8.7 and at a temperature of 25 °C. Metabolic significance of the catalyzed reaction The main product, glucose-1,6-bisphosphate, appears to have several functions: 1. Inhibition of hexokinase, an enzyme used in the first step of glycolysis. 2. Activation of phosphofructokinase-1 (PFK-1) and pyruvate kinase, both of which are en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatidylinositol (3,5)-bisphosphate
Phosphatidylinositol 3,5-bisphosphate (PtdIns(3,5)P2) is one of the seven phosphoinositides found in eukaryotic cell membranes. In quiescent cells, the PtdIns(3,5)P2 levels, typically quantified by HPLC, are the lowest amongst the constitutively present phosphoinositides. They are approximately 3 to 5-fold lower as compared to PtdIns3P and PtdIns5P ( Phosphatidylinositol 5-phosphate) levels, and more than 100-fold lower than the abundant PtdIns4P ( Phosphatidylinositol 4-phosphate) and PtdIns(4,5)P2. PtdIns(3,5)P2 was first reported to occur in mouse fibroblasts and budding yeast S. cerevisiae in 1997.Whiteford CC, Brearley CA, Ulug ET. Phosphatidylinositol 3,5-bisphosphate defines a novel PI 3-kinase pathway in resting mouse fibroblasts. Biochem J. 1997 May 1;323 ( Pt 3):597-601. In S. cerevisiae PtdIns(3,5)P2 levels increase dramatically during hyperosmotic shock.Dove SK, Cooke FT, Douglas MR, Sayers LG, Parker PJ, Michell RH. Osmotic stress activates phosphatidylinositol-3,5- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fructose 2,6-bisphosphate
Fructose 2,6-bisphosphate, abbreviated Fru-2,6-''P''2, is a metabolite that allosterically affects the activity of the enzymes phosphofructokinase 1 (PFK-1) and fructose 1,6-bisphosphatase (FBPase-1) to regulate glycolysis and gluconeogenesis. Fru-2,6-''P''2 itself is synthesized and broken down by the bifunctional enzyme phosphofructokinase 2/ fructose-2,6-bisphosphatase (PFK-2/FBPase-2). The synthesis of Fru-2,6-''P''2 is performed through a bifunctional enzyme containing both PFK-2 and FBPase-2, which is dephosphorylated, allowing the PFK-2 portion to phosphorylate fructose 6-phosphate using ATP. The breakdown of Fru-2,6-''P''2 is catalyzed by the phosphorylation of the bifunctional enzyme, which allows FBPase-2 to dephosphorylate fructose 2,6-bisphosphate to produce fructose 6-phosphate and Pi. Effects on glucose metabolism Fru-2,6-''P''2 strongly activates glucose breakdown in glycolysis through allosteric modulation (activation) of phosphofructokinase 1 (PFK-1). Elevate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribulose 1,5-bisphosphate
Ribulose 1,5-bisphosphate (RuBP) is an organic substance that is involved in photosynthesis, notably as the principal acceptor in plants. It is a colourless anion, a double phosphate ester of the ketopentose (ketone-containing sugar with five carbon atoms) called ribulose. Salts of RuBP can be isolated, but its crucial biological function happens in solution. RuBP occurs not only in plants but in all domains of life, including Archaea, Bacteria, and Eukarya. History RuBP was originally discovered by Andrew Benson in 1951 while working in the lab of Melvin Calvin at UC Berkeley. Calvin, who had been away from the lab at the time of discovery and was not listed as a co-author, controversially removed the full molecule name from the title of the initial paper, identifying it solely as "ribulose". At the time, the molecule was known as ''ribulose diphosphate'' (RDP or RuDP) but the prefix di- was changed to bis- to emphasize the nonadjacency of the two phosphate groups. Role in ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fructose 1,6-bisphosphate
Fructose 1,6-bisphosphate, also known as Harden-Young ester, is fructose sugar phosphorylated on carbons 1 and 6 (i.e., is a fructosephosphate). The β-D-form of this compound is common in cells. Upon entering the cell, most glucose and fructose is converted to fructose 1,6-bisphosphate. In glycolysis Fructose 1,6-bisphosphate lies within the glycolysis metabolic pathway and is produced by phosphorylation of fructose 6-phosphate. It is, in turn, broken down into two compounds: glyceraldehyde 3-phosphate and dihydroxyacetone phosphate. It is an allosteric activator of pyruvate kinase through distinct interactions of binding and allostery at the enzyme's catalytic site ''The numbering of the carbon atoms indicates the fate of the carbons according to their position in fructose 6-phosphate.'' Isomerism Fructose 1,6-bisphosphate has only one biologically active isomer, the β-D-form. There are many other isomers, analogous to those of fructose. Iron chelation Fructos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fructose-2,6-bisphosphate 6-phosphatase
The enzyme fructose-2,6-bisphosphate 6-phosphatase (EC 3.1.3.54) catalyzes the reaction :β-D-fructose 2,6-bisphosphate + H2O \rightleftharpoons β-D-fructofuranose 2-phosphate + phosphate This enzyme belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name of this enzyme class is β-D-fructose-2,6-bisphosphate 6-phosphohydrolase. Other names in common use include fructose 2,6-bisphosphate-6-phosphohydrolase, fructose-2,6-bisphosphate 6-phosphohydrolase, and D-fructose-2,6-bisphosphate 6-phosphohydrolase. This enzyme participates in fructose and mannose metabolism Mannose is a sugar monomer of the aldohexose series of carbohydrates. It is a C-2 epimer of glucose. Mannose is important in human metabolism, especially in the glycosylation of certain proteins. Several congenital disorders of glycosylation .... References * * EC 3.1.3 Enzymes of unknown structure {{3.1-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatidylinositol (4,5)-bisphosphate
Phosphatidylinositol 4,5-bisphosphate or PtdIns(4,5)''P''2, also known simply as PIP2 or PI(4,5)P2, is a minor phospholipid component of cell membranes. PtdIns(4,5)''P''2 is enriched at the plasma membrane where it is a substrate for a number of important signaling proteins. PIP2 also forms lipid clusters that sort proteins. PIP2 is formed primarily by the type I phosphatidylinositol 4-phosphate 5-kinases from PI(4)P. In metazoans, PIP2 can also be formed by type II phosphatidylinositol 5-phosphate 4-kinases from PI(5)P. The fatty acids of PIP2 are variable in different species and tissues, but the most common fatty acids are stearic in position 1 and arachidonic in 2. Signaling pathways PIP2 is a part of many cellular signaling pathways, including PIP2 cycle, PI3K signalling, and PI5P metabolism. Recently, it has been found in the nucleus with unknown function. Functions Cytoskeleton dynamics near membranes PIP2 regulates the organization, polymerization, and bran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatidylinositol-3,4-bisphosphate 4-phosphatase
The enzyme phosphatidylinositol-3,4-bisphosphate 4-phosphatase (EC 3.1.3.66) that catalyzes the reaction :1-phosphatidyl-''myo''-inositol 3,4-bisphosphate + H2O \rightleftharpoons 1-phosphatidyl-1D-''myo''-inositol 3-phosphate + phosphate This enzyme belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name is 1-phosphatidyl-1D-''myo''-inositol-3,4-bisphosphate 4-phosphohydrolase. Other names in common use include inositol-3,4-bisphosphate 4-phosphatase, D-''myo''-inositol-3,4-bisphosphate 4-phosphohydrolase, phosphoinositide 4-phosphatase, inositol polyphosphate 4-phosphatase, D-''myo''-inositol-3,4-bisphosphate 4-phosphohydrolase, and inositol polyphosphate 4-phosphatase type II. This enzyme participates in inositol phosphate metabolism Inositol phosphates are a group of mono- to hexaphosphorylated inositols. They play crucial roles in diverse cellular functions, such as cell growth, apoptosis, cell migration, endocy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatidylinositol (3,4)-bisphosphate
Phosphatidylinositol (3,4)-bisphosphate (PtdIns(3,4)''P''2) is a minor phospholipid component of cell membranes, yet an important second messenger. The generation of PtdIns(3,4)''P''2 at the plasma membrane activates a number of important cell signaling pathways. Of all the phospholipids found within the membrane, inositol phospholipids make up less than 10%. Phosphoinositide’s (PI’s) also known as phosphatidylinositol phosphates, are synthesized in the cells endoplasmic reticulum by the protein phosphatidylinositol synthase (PIS). PI’s are highly compartmentalized, their main components include a glycerol backbone, two fatty acid chains enriched with stearic acid and arachidonic acid, and an inositol ring whose phosphate groups regulation differs between organelles depending on the specific PI and PIP kinases and PIP phosphatases present in the organelle (Image 1). These kinases and phosphatases conduct phosphorylation and dephosphorylation at the inositol sugar head groups ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatidylinositol-4,5-bisphosphate 3-kinase
In enzymology, a phosphatidylinositol-4,5-bisphosphate 3-kinase () is an enzyme that catalyzes the chemical reaction: :ATP + 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate \rightleftharpoons ADP + 1-phosphatidyl-1D-myo-inositol 3,4,5-trisphosphate Thus, the two substrates of this enzyme are ATP and 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate, whereas its two products are ADP and 1-phosphatidyl-1D-myo-inositol 3,4,5-trisphosphate. This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing groups (phosphotransferases) with an alcohol group as acceptor. The systematic name of this enzyme class is ATP:1-phosphatidyl-1D-myo-inositol-4,5-bisphosphate 3-phosphotransferase. This enzyme is also called type I phosphoinositide 3-kinase. This enzyme participates in 29 metabolic pathways: inositol phosphate metabolism, erbb signaling pathway, phosphatidylinositol signaling system, mtor signaling pathway, apoptosis, VEGF signaling path ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3'(2'),5'-bisphosphate Nucleotidase
The enzyme 3′(2′),5′-bisphosphate nucleotidase (EC 3.1.3.7) catalyzes the reaction :adenosine 3′,5′-bisphosphate + H2O \rightleftharpoons AMP + phosphate This enzyme belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name is adenosine-3′(2′),5′-bisphosphate 3′(2′)-phosphohydrolase. Other names in common use include phosphoadenylate 3′-nucleotidase, 3′-phosphoadenylylsulfate 3′-phosphatase, and 3′(2′),5′-bisphosphonucleoside 3′(2′)-phosphohydrolase. This enzyme participates in sulfur metabolism. Structural studies As of late 2007, 6 structures A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such as ... have been solved for this class of enzymes, with PDB accession codes , , , , , and . Refere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fructose-2,6-bisphosphate 2-phosphatase
The enzyme fructose-2,6-bisphosphate 2-phosphatase ({EC 3.1.3.46) catalyzes the reaction :β-D-fructose 2,6-bisphosphate + H2O \rightleftharpoons D-fructose 6-phosphate + phosphate This enzyme belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name is β-D-fructose-2,6-bisphosphate 2-phosphohydrolase. Other names in common use include fructose-2,6-bisphosphatase, and D-fructose-2,6-bisphosphate 2-phosphohydrolase. This enzyme participates in fructose and mannose metabolism Mannose is a sugar monomer of the aldohexose series of carbohydrates. It is a C-2 epimer of glucose. Mannose is important in human metabolism, especially in the glycosylation of certain proteins. Several congenital disorders of glycosylation .... Structural studies As of late 2007, 13 structures have been solved for this class of enzymes, with PDB accession codes , , , , , , , , , , , , and . References * EC 3.1.3 Enzymes of know ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
