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Methyl-ONN-azoxymethanol Beta-D-glucosyltransferase
In enzymology, a methyl-ONN-azoxymethanol beta-D-glucosyltransferase () is an enzyme that catalyzes the chemical reaction :UDP-glucose + methyl-ONN-azoxymethanol \rightleftharpoons UDP + cycasin Thus, the two substrates of this enzyme are UDP-glucose and methyl-ONN-azoxymethanol, whereas its two products are UDP and cycasin. This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ... of this enzyme class is UDP-glucose:methyl-ONN-azoxymethanol beta-D-glucosyltransferase. Other names in common use include cycasin synthase, uridine diphosphoglucose-methylazoxymethanol glucosyltransferase, and UDP-glucose-methylazoxymethanol glucosyltransferase. References * EC 2.4. ... [...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] |
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] |
Catalysis
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reaction
A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the Atomic nucleus, nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive Chemical element, elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reagent, reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more Product (chemistry), products, which usually have properties different from the reactants. Reactions often consist of a sequence o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (biochemistry)
In chemistry, the term substrate is highly context-dependent. Broadly speaking, it can refer either to a chemical species being observed in a chemical reaction, or to a surface on which other chemical reactions or microscopy are performed. In the former sense, a reagent is added to the ''substrate'' to generate a product through a chemical reaction. The term is used in a similar sense in synthetic and organic chemistry, where the substrate is the chemical of interest that is being modified. In biochemistry, an enzyme substrate is the material upon which an enzyme acts. When referring to Le Chatelier's principle, the substrate is the reagent whose concentration is changed. ;Spontaneous reaction : :*Where S is substrate and P is product. ;Catalysed reaction : :*Where S is substrate, P is product and C is catalyst. In the latter sense, it may refer to a surface on which other chemical reactions are performed or play a supporting role in a variety of spectroscopic and microscop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UDP-glucose
Uridine diphosphate glucose (uracil-diphosphate glucose, UDP-glucose) is a nucleotide sugar. It is involved in glycosyltransferase reactions in metabolism. Functions UDP-glucose is used in nucleotide sugar metabolism as an activated form of glucose, a substrate for enzymes called glucosyltransferases. UDP-glucose is a precursor of glycogen and can be converted into UDP-galactose and UDP-glucuronic acid, which can then be used as substrates by the enzymes that make polysaccharides containing galactose and glucuronic acid. UDP-glucose can also be used as a precursor of sucrose, lipopolysaccharides and glycosphingolipids. Components UDP-glucose consists of the pyrophosphate group, ribose, glucose, and uracil. See also * DNA * Nucleoside * Nucleotide * Oligonucleotide * RNA * TDP-glucose * Uracil * 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 pyro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl-ONN-azoxymethanol
Methylazoxymethanol acetate, MAM, is a neurotoxin which reduces DNA synthesis used in making animal models of neurological diseases including schizophrenia and epilepsy. MAM is found in cycad seeds, and causes zamia staggers. It selectively targets neuroblasts in the central nervous system. In rats, administration of MAM affects structures in the brain which are developing most quickly. It is an acetate of methylazoxymethanol. MAM animal models Schizophrenia In rat models, the specific effect of MAM on neural development depends on the gestational age of the subject. At the seventeenth gestational day (GD17), administration of MAM produces behavioral and histopathological patterns found in schizophrenia. The molecular mechanism behind this model is not fully known. Methylazoxymethanol acetate administered at GD17 reduces the thickness of the hippocampus and the thalamus. The locomotor effects of amphetamines and the spontaneous firing rate of dopaminergic neurons in the ventral teg ... [...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] |
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] |
Cycasin
Cycasin is a carcinogenic and neurotoxic glucoside found in cycads such as ''Cycas revoluta'' and ''Zamia pumila''. Symptoms of poisoning include vomiting, diarrhea, weakness, seizures, and hepatotoxicity. In metabolic conditions, cycasin is hydrolyzed into glucose and methylazoxymethanol (MAM), the latter of which dissociates into formaldehyde and diazomethane. It induces hepatotoxicity and Zamia staggers, a fatal nervous disease affecting cattle resulting from browsing on the leaves or other parts of cycads. Sources Cycasin is found in all known cycad genera and is distributed throughout the body of the plant, but with the highest concentration in the seeds. It is one of several toxins found in cycad plants, along with the neurotoxic amino acid BMAA. The origin and biological role of these toxins is unknown, as there does not appear to be a statistically significant correlation between the concentration of toxic material and the types of herbivory observed in animals consuming th ... [...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] |
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] |
