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Lactosylceramide 1,3-N-acetyl-beta-D-glucosaminyltransferase
In enzymology, a lactosylceramide 1,3-N-anning-beta-D-glrofelucosaminyltlolferase () is an enzyme that catalyzes the chemical reaction :UDP-N-acetyl-D-glucosamine + D-galactosyl-1,4-beta-D-glucosylceramide \rightleftharpoons UDP + N-acetyl-D-glucosaminyl-1,3-beta-D-galactosyl-1,4-beta-D- glucosylceramide Thus, the two substrates of this enzyme are UDP-N-acetyl-D-glucosamine and D-galactosyl-1,4-beta-D-glucosylceramide, whereas its 3 products are UDP, N-acetyl-D-glucosaminyl-1,3-beta-D-galactosyl-1,4-beta-D-, and glucosylceramide. This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is UDP-N-acetyl-D-glucosamine:D-galactosyl-1,4-beta-D-glucosylceramide beta-1,3-acetylglucosaminyltransferase. Other names in common use include LA2 synthase, beta1->3-N-acetylglucosaminyltransferase, uridine diphosphoacetylglucosamine-lactosylceramide, beta-acetylglucosaminyltransferase, and lactosylceramide beta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzymology
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucosylceramide
Glucocerebroside (also called glucosylceramide) is any of the cerebrosides in which the monosaccharide head group is glucose. Clinical significance In Gaucher disease, the enzyme glucocerebrosidase is nonfunctional and cannot break down glucocerebroside into glucose and ceramide in the lysosome. Affected macrophages Macrophages (abbreviated as M φ, MΦ or MP) ( el, large eaters, from Greek ''μακρός'' (') = large, ''φαγεῖν'' (') = to eat) are a type of white blood cell of the immune system that engulfs and digests pathogens, such as cancer ce ..., called Gaucher cells, have a distinct appearance similar to "wrinkled tissue paper" under light microscopy, because the substrates build-up within the lysosome. See also * Glucosylceramide synthase * Gauchers disease * Glucocerebrosidase References External links * * Glycolipids Carbohydrates {{biochem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycan Structures - Biosynthesis 2
The terms glycans and polysaccharides are defined by IUPAC as synonyms meaning "compounds consisting of a large number of monosaccharides linked glycosidically". However, in practice the term glycan may also be used to refer to the carbohydrate portion of a glycoconjugate, such as a glycoprotein, glycolipid, or a proteoglycan, even if the carbohydrate is only an oligosaccharide. Glycans usually consist solely of O-glycosidic linkages of monosaccharides. For example, cellulose is a glycan (or, to be more specific, a glucan) composed of β-1,4-linked D-glucose, and chitin is a glycan composed of β-1,4-linked ''N''-acetyl-D-glucosamine. Glycans can be homo- or heteropolymers of monosaccharide residues, and can be linear or branched. Glycans and proteins Glycans can be found attached to proteins as in glycoproteins and proteoglycans. In general, they are found on the exterior surface of cells. O- and N-linked glycans are very common in eukaryotes but may also be found, although ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosphingolipid Biosynthesis - Neo-lactoseries
Glycosphingolipids are a subtype of glycolipids containing the amino alcohol sphingosine. They may be considered as sphingolipids with an attached carbohydrate. Glycosphingolipids are a group of lipids (more specifically, sphingolipids) and are a part of the cell membrane. They consist of a hydrophobic ceramide part and a glycosidically bound carbohydrate part. This oligosaccharide content remains on the outside of the cell membrane where it is important for biological processes such as cell adhesion or cell–cell interactions. Glycosphingolipids play also important role in oncogenesis and ontogenesis. Classification In general, glycosphingolipids can be categorized into two groups: neutral glycosphingolipids (also called glycosphingolipids) and negatively charged glycosphingolipids. The latter can be distinguished again by means of the charge carrier. While in gangliosides sialic acids are found, sulfatides have a sulfate group. The structural similarity of most gly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosphingolipid Biosynthesis - Lactoseries
Glycosphingolipids are a subtype of glycolipids containing the amino alcohol sphingosine. They may be considered as sphingolipids with an attached carbohydrate. Glycosphingolipids are a group of lipids (more specifically, sphingolipids) and are a part of the cell membrane. They consist of a hydrophobic ceramide part and a glycosidic bond, glycosidically bound carbohydrate part. This oligosaccharide content remains on the outside of the cell membrane where it is important for biological processes such as cell adhesion or cell–cell interactions. Glycosphingolipids play also important role in oncogenesis and ontogenesis. Classification In general, glycosphingolipids can be categorized into two groups: neutral glycosphingolipids (also called glycosphingolipids) and negatively charged glycosphingolipids. The latter can be distinguished again by means of the charge carrier. While in gangliosides sialic acids are found, sulfatides have a sulfate group. The structural similarity of most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolism
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks for proteins, lipids, nucleic acids, and some carbohydrates; and the elimination of metabolic wastes. These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their structures, and respond to their environments. The word metabolism can also refer to the sum of all chemical reactions that occur in living organisms, including digestion and the transportation of substances into and between different cells, in which case the above described set of reactions within the cells is called intermediary (or intermediate) metabolism. Metabolic reactions may be categorized as ''catabolic'' – the ''breaking down'' of compounds (for example, of glucose to pyruvate by ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Enzymes
This article lists enzymes by their classification in the International Union of Biochemistry and Molecular Biology's Enzyme Commission (EC) numbering system. * List of EC numbers (EC 5) * List of EC numbers (EC 6) :Oxidoreductases (EC 1) (Oxidoreductase) *Dehydrogenase * Luciferase *DMSO reductase :EC 1.1 (act on the CH-OH group of donors) * :EC 1.1.1 (with NAD+ or NADP+ as acceptor) ** Alcohol dehydrogenase (NAD) ** Alcohol dehydrogenase (NADP) **Homoserine dehydrogenase ** Aminopropanol oxidoreductase **Diacetyl reductase **Glycerol dehydrogenase **Propanediol-phosphate dehydrogenase ** glycerol-3-phosphate dehydrogenase (NAD+) ** D-xylulose reductase **L-xylulose reductase **Lactate dehydrogenase **Malate dehydrogenase **Isocitrate dehydrogenase ** HMG-CoA reductase * :EC 1.1.2 (with a cytochrome as acceptor) * :EC 1.1.3 (with oxygen as acceptor) **Glucose oxidase **L-gulonolactone oxidase **Thiamine oxidase **Xanthine oxidase * :EC 1.1.4 (with a disul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosyltransferase
Glycosyltransferases (GTFs, Gtfs) are enzymes ( EC 2.4) that establish natural glycosidic linkages. They catalyze the transfer of saccharide moieties from an activated nucleotide sugar (also known as the "glycosyl donor") to a nucleophilic glycosyl acceptor molecule, the nucleophile of which can be oxygen- carbon-, nitrogen-, or sulfur-based. The result of glycosyl transfer can be a carbohydrate, glycoside, oligosaccharide, or a polysaccharide. Some glycosyltransferases catalyse transfer to inorganic phosphate or water. Glycosyl transfer can also occur to protein residues, usually to tyrosine, serine, or threonine to give O-linked glycoproteins, or to asparagine to give N-linked glycoproteins. Mannosyl groups may be transferred to tryptophan to generate C-mannosyl tryptophan, which is relatively abundant in eukaryotes. Transferases may also use lipids as an acceptor, forming glycolipids, and even use lipid-linked sugar phosphate donors, such as dolichol phosphates in eukaryotic o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uridine Diphosphate
Uridine diphosphate, abbreviated UDP, is a nucleotide diphosphate. It is an ester of pyrophosphoric acid with the nucleoside uridine. UDP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase uracil. UDP is an important factor in glycogenesis. Before glucose can be stored as glycogen in the liver and muscles, the enzyme UDP-glucose pyrophosphorylase forms a UDP-glucose unit by combining glucose 1-phosphate with uridine triphosphate, cleaving a pyrophosphate ion in the process. Then, the enzyme glycogen synthase combines UDP-glucose units to form a glycogen chain. The UDP molecule is cleaved from the glucose ring during this process and can be reused by UDP-glucose pyrophosphorylase. See also * DNA * Nucleoside * Nucleotide * Oligonucleotide * RNA * UGGT UGGT, or UDP-glucose:glycoprotein glucosyltransferase, is a soluble enzyme resident in the lumen of the endoplasmic reticulum (ER). The main function of UGGT is to recognize misfolded glycoprotein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Product (chemistry)
Products are the species formed from chemical reactions. During a chemical reaction, reactants are transformed into products after passing through a high energy transition state. This process results in the consumption of the reactants. It can be a spontaneous reaction or mediated by catalysts which lower the energy of the transition state, and by solvents which provide the chemical environment necessary for the reaction to take place. When represented in chemical equations, products are by convention drawn on the right-hand side, even in the case of reversible reactions. The properties of products such as their energies help determine several characteristics of a chemical reaction, such as whether the reaction is exergonic or endergonic. Additionally, the properties of a product can make it easier to extract and purify following a chemical reaction, especially if the product has a different state of matter than the reactants. Spontaneous reaction : R \rightarrow P *Where R is r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
