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Glycerol 3-phosphate
''sn''-Glycerol 3-phosphate is the organic ion with the formula HOCH2CH(OH)CH2OPO32-. It is one of three stereoisomers of the ester of dibasic phosphoric acid (HOPO32-) and glycerol. It is a component of glycerophospholipids. Equally appropriate names in biochemical context include glycerol-3-phosphate, 3-''O''-phosphonoglycerol, 3-phosphoglycerol; and Gro3P. From a historical reason, it is also known as -glycerol 3-phosphate, -glycerol 1-phosphate, -α-glycerophosphoric acid. Biosynthesis Glycerol 3-phosphate is synthesized by reducing dihydroxyacetone phosphate (DHAP), an intermediate in glycolysis. The reduction is catalyzed by glycerol-3-phosphate dehydrogenase. DHAP and thus glycerol 3-phosphate can also be synthesized from amino acids and citric acid cycle intermediates via the glyceroneogenesis pathway. : + NAD(P)H + H+ → + NAD(P)+ It is also synthesized by the phosphorylation of glycerol, which is generated by hydrolysis of fats. This esterification is catal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycerol 1-phosphate
''sn''-Glycerol 1-phosphate is the conjugate base of a phosphoric ester of glycerol. It is a component of ether lipids, which are common for archaea. Biosynthesis and metabolism Glycerol 1-phosphate is synthesized by reducing dihydroxyacetone phosphate (DHAP), a glycolysis intermediate, with ''sn''-glycerol-1-phosphate dehydrogenase. DHAP and thus glycerol 1-phosphate is also possible to be synthesized from amino acids and citric acid cycle intermediates via gluconeogenesis pathway. : + NAD(P)H + H+ → + NAD(P)+ Glycerol 1-phosphate is a starting material for ''de novo'' synthesis of ether lipids, such as those derived from archaeol and caldarchaeol. It is first geranylgeranylated on its ''sn''-3 position by a cytosolic enzyme, phosphoglycerol geranylgeranyltransferase. A second geranylgeranyl group is then added on the ''sn''-2 position making unsaturated archaetidic acid. Enantiomer Organisms other than archaea, i.e. bacteria and eucarya, use the enantiomer I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorylation
In chemistry, phosphorylation is the attachment of a phosphate group to a molecule or an ion. This process and its inverse, dephosphorylation, are common in biology and could be driven by natural selection. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License. Protein phosphorylation often activates (or deactivates) many enzymes. Glucose Phosphorylation of sugars is often the first stage in their catabolism. Phosphorylation allows cells to accumulate sugars because the phosphate group prevents the molecules from diffusing back across their transporter. Phosphorylation of glucose is a key reaction in sugar metabolism. The chemical equation for the conversion of D-glucose to D-glucose-6-phosphate in the first step of glycolysis is given by :D-glucose + ATP → D-glucose-6-phosphate + ADP : ΔG° = −16.7 kJ/mol (° indicates measurement at standard condition) Hepatic cells are freely permeable to glucose, and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycerol-1-phosphatase
The enzyme glycerol-1-phosphatase (EC 3.1.3.21) catalyzes the reaction :glycerol 1-phosphate + H2O \rightleftharpoons glycerol + phosphate This enzyme belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name is glycerol-1-phosphate phosphohydrolase. Other names in common use include α-glycerophosphatase, α-glycerol phosphatase, glycerol 3-phosphatase, glycerol-3-phosphate phosphatase, and glycerol 3-phosphate phosphohydrolase. This enzyme participates in glycerolipid metabolism. Among the organisms that have been shown to express this enzymatic activity are ''A. thaliana'' (plant) via the ''AtSgpp'' and ''AtGpp'' gene products; '' D. salina'' (alga); ''S. cerevisiae'' (fungus) via the ''GPP1/RHR2/YIL053W'' and ''GPP2/HOR2/YER062C'' gene products; '' C. albicans'' (fungus) via the ''GPP1'' gene product; '' M. tuberculosis'' (bacteria) via the ''rv1692'' gene product; and C57BL/6N mice and Wistar rat A laboratory ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coenzyme A
Coenzyme A (CoA, SHCoA, CoASH) is a coenzyme, notable for its role in the synthesis and oxidation of fatty acids, and the oxidation of pyruvate in the citric acid cycle. All genomes sequenced to date encode enzymes that use coenzyme A as a substrate, and around 4% of cellular enzymes use it (or a thioester) as a substrate. In humans, CoA biosynthesis requires cysteine, pantothenate (vitamin B5), and adenosine triphosphate (ATP). In its acetyl form, coenzyme A is a highly versatile molecule, serving metabolic functions in both the anabolic and catabolic pathways. Acetyl-CoA is utilised in the post-translational regulation and allosteric regulation of pyruvate dehydrogenase and carboxylase to maintain and support the partition of pyruvate synthesis and degradation. Discovery of structure Coenzyme A was identified by Fritz Lipmann in 1946, who also later gave it its name. Its structure was determined during the early 1950s at the Lister Institute, London, together by Li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lysophosphatidic Acid
Lysophosphatidic acid (LPA) is a phospholipid derivative that can act as a signaling molecule. Function LPA acts as a potent mitogen due to its activation of three high-affinity G-protein-coupled receptors called LPAR1, LPAR2, and LPAR3 (also known as EDG2, EDG4, and EDG7). Additional, newly identified LPA receptors include LPAR4 (P2RY9, GPR23), LPAR5 (GPR92) and LPAR6 (P2RY5, GPR87). Clinical significance Because of its ability to stimulate cell proliferation, aberrant LPA-signaling has been linked to cancer in numerous ways. Dysregulation of autotaxin or the LPA receptors can lead to hyperproliferation, which may contribute to oncogenesis and metastasis. LPA may be the cause of pruritus (itching) in individuals with cholestatic (impaired bile flow) diseases. GTPase activation Downstream of LPA receptor activation, the small GTPase Rho can be activated, subsequently activating Rho kinase. This can lead to the formation of stress fibers and cell migration through t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acyl-CoA
Acyl-CoA is a group of coenzymes that metabolize fatty acids. Acyl-CoA's are susceptible to beta oxidation, forming, ultimately, acetyl-CoA. The acetyl-CoA enters the citric acid cycle, eventually forming several equivalents of ATP. In this way, fats are converted to ATP, the universal biochemical energy carrier. Functions Fatty acid activation Fats are broken down by conversion to acyl-CoA. This conversion is one response to high energy demands such as exercise. The oxidative degradation of fatty acids is a two-step process, catalyzed by acyl-CoA synthetase. Fatty acids are converted to their acyl phosphate, the precursor to acyl-CoA. The latter conversion is mediated by acyl-CoA synthase" :acyl-P + HS-CoA → acyl-S-CoA + Pi + H+ Three types of acyl-CoA synthases are employed, depending on the chain length of the fatty acid. For example, the substrates for medium chain acyl-CoA synthase are 4-11 carbon fatty acids. The enzyme acyl-CoA thioesterase takes of the acyl-CoA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatidic Acid
Phosphatidic acids are anionic phospholipids important to cell signaling and direct activation of lipid-gated ion channels. Hydrolysis of phosphatidic acid gives rise to one molecule each of glycerol and phosphoric acid and two molecules of fatty acids. They constitute about 0.25% of phospholipids in the bilayer. Structure Phosphatidic acid consists of a glycerol backbone, with, in general, a saturated fatty acid bonded to carbon-1, an unsaturated fatty acid bonded to carbon-2, and a phosphate group bonded to carbon-3. Formation and degradation Besides de novo synthesis, PA can be formed in three ways: * By phospholipase D (PLD), via the hydrolysis of the P-O bond of phosphatidylcholine (PC) to produce PA and choline. * By the phosphorylation of diacylglycerol (DAG) by DAG kinase (DAGK). * By the acylation of lysophosphatidic acid by lysoPA-acyltransferase (LPAAT); this is the most common pathway.Devlin, T. M. 2004. ''Bioquímica'', 4ª edición. Reverté, Barcelona. The glyce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycerol-3-phosphate O-acyltransferase
In enzymology, a glycerol-3-phosphate O-acyltransferase () is an enzyme that catalyzes the chemical reaction :acyl-CoA + sn-glycerol 3-phosphate \rightleftharpoons CoA + 1-acyl-sn-glycerol 3-phosphate Thus, the two substrates of this enzyme are acyl-CoA and sn-glycerol 3-phosphate, whereas its two products are CoA and 1-acyl-sn-glycerol 3-phosphate. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acyl-CoA:sn-glycerol-3-phosphate 1-O-acyltransferase. Other names in common use include alpha-glycerophosphate acyltransferase, 3-glycerophosphate acyltransferase, ACP:sn-glycerol-3-phosphate acyltransferase, glycerol 3-phosphate acyltransferase, glycerol phosphate acyltransferase, glycerol phosphate transacylase, glycerophosphate acyltransferase, glycerophosphate transacylase, sn-glycerol 3-phosphate acyltransferase, and sn-glycerol-3-phosphate acyltr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryotes
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard archaea. This implies that there are only two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as flagellated phagotrophs. Their name comes from the Greek εὖ (''eu'', "well" or "good") and κάρυον (''karyon'', "nut" or "kernel"). Euk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycerolipid
Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include storing energy, signaling, and acting as structural components of cell membranes. Lipids have applications in the cosmetic and food industries, and in nanotechnology. Lipids may be broadly defined as hydrophobic or amphiphilic small molecules; the amphiphilic nature of some lipids allows them to form structures such as vesicles, multilamellar/unilamellar liposomes, or membranes in an aqueous environment. Biological lipids originate entirely or in part from two distinct types of biochemical subunits or "building-blocks": ketoacyl and isoprene groups. Using this approach, lipids may be divided into eight categories: fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, and polyketides (derived from condensation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phospholipid
Phospholipids, are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). Marine phospholipids typically have omega-3 fatty acids EPA and DHA integrated as part of the phospholipid molecule. The phosphate group can be modified with simple organic molecules such as choline, ethanolamine or serine. Phospholipids are a key component of all cell membranes. They can form lipid bilayers because of their amphiphilic characteristic. In eukaryotes, cell membranes also contain another class of lipid, sterol, interspersed among the phospholipids. The combination provides fluidity in two dimensions combined with mechanical strength against rupture. Purified phospholipids are produced commercially and have found applications in nanotechnology and materials science. The first phospholipid identified in 1847 as such in biological tissues wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosine Diphosphate
Adenosine diphosphate (ADP), also known as adenosine pyrophosphate (APP), is an important organic compound in metabolism and is essential to the flow of energy in living cells. ADP consists of three important structural components: a sugar backbone attached to adenine and two phosphate groups bonded to the 5 carbon atom of ribose. The diphosphate group of ADP is attached to the 5’ carbon of the sugar backbone, while the adenine attaches to the 1’ carbon. ADP can be interconverted to adenosine triphosphate (ATP) and adenosine monophosphate (AMP). ATP contains one more phosphate group than does ADP. AMP contains one fewer phosphate group. Energy transfer used by all living things is a result of dephosphorylation of ATP by enzymes known as ATPases. The cleavage of a phosphate group from ATP results in the coupling of energy to metabolic reactions and a by-product of ADP. ATP is continually reformed from lower-energy species ADP and AMP. The biosynthesis of ATP is achieved through ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
