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Azoreductase
Azobenzene reductase also known as azoreductase () is an enzyme that catalyzes the chemical reaction: :N,N-dimethyl-1,4-phenylenediamine + aniline + NADP+ \rightleftharpoons 4-(dimethylamino)azobenzene + NADPH + H+ The 3 substrates of this enzyme are N,N-dimethyl- 1,4-phenylenediamine, aniline, and nicotinamide adenine dinucleotide phosphate ion, whereas its 3 products are 4-(dimethylamino)azobenzene, nicotinamide adenine dinucleotide phosphate, and hydrogen ion. This enzyme belongs to the family of oxidoreductases, specifically those acting on other nitrogenous compounds as donors with NAD+ or NADP+ as acceptor. Mechanism The reaction catalyzed by this enzyme proceeds via a ping-pong mechanism by using 2 equivalents of NAD(P)H to reduce one equivalent of the azo compound substrate (for example methyl red where Ar = ''p''-dimethylaniline and Ar' = ''o''-benzoic acid) into two equivalents of aniline product: : Ar–N=N–Ar' + 2(NAD(P)H + H+) \rightleftharpoons Ar–NH2 + NH ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), 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, 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 include Ribozyme, catalytic RNA molecules, also called ribozymes. They are sometimes descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Red
Methyl red (2-(''N'',''N''-dimethyl-4-aminophenyl) azobenzenecarboxylic acid), also called C.I. Acid Red 2, is an indicator dye that turns red in acidic solutions. It is an azo dye, and is a dark red crystalline powder. Methyl red is a pH indicator; it is red in pH under 4.4, yellow in pH over 6.2, and orange in between, with a p''K''a of 5.1. Murexide and methyl red are investigated as promising enhancers of sonochemical destruction of chlorinated hydrocarbon pollutants. Methyl red is classed by the IARC in group 3 - unclassified as to carcinogenic potential in humans. Preparation As an azo dye, methyl red may be prepared by diazotization of anthranilic acid, followed by reaction with dimethylaniline: : Properties The color of methyl red is pH dependent, because protonation causes it to adopt a hydrazone/quinone structure. : Methyl Red has a special use in histopathology for showing acidic nature of tissue and presence of organisms with acidic natured cell walls. Meth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EC 1
EC or ec may refer to: Arts and entertainment * EC Comics, an American publisher of comic books * '' Electric Circus'', a Canadian television program * Eric Clapton Stratocaster, signature model guitars by Fender Businesses and organisations Government * Environment and Climate Change Canada, a Canadian federal government department * European Commission, the executive body of the European Union * European Council, the European Union institution comprising the college of heads of state of government * European Communities, one of the three pillars of the EU * European Community, a significant component of the European Union from 1993 to 2009, renamed European Economic Community Transportation * EuroCity, a train service of the European inter-city rail network * EasyJet Europe (IATA code: EC) * Avialeasing (former IATA code: EC), a cargo airline * East Coast (train operating company), a train operating company in the UK * EC, the aircraft registration prefix for Spain Ed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Data Bank
The Protein Data Bank (PDB) is a database for the three-dimensional structural data of large biological molecules such as proteins and nucleic acids, which is overseen by the Worldwide Protein Data Bank (wwPDB). This structural data is obtained and deposited by biologists and biochemists worldwide through the use of experimental methodologies such as X-ray crystallography, Nuclear magnetic resonance spectroscopy of proteins, NMR spectroscopy, and, increasingly, cryo-electron microscopy. All submitted data are reviewed by expert Biocuration, biocurators and, once approved, are made freely available on the Internet under the CC0 Public Domain Dedication. Global access to the data is provided by the websites of the wwPDB member organizations (PDBe, PDBj, RCSB PDB, and BMRB). The PDB is a key in areas of structural biology, such as structural genomics. Most major scientific journals and some funding agencies now require scientists to submit their structure data to the PDB. Many other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tertiary Structure
Protein tertiary structure is the three-dimensional shape of a protein. The tertiary structure will have a single polypeptide chain "backbone" with one or more protein secondary structures, the protein domains. Amino acid side chains and the backbone may interact and bond in a number of ways. The interactions and bonds of side chains within a particular protein determine its tertiary structure. The protein tertiary structure is defined by its atomic coordinates. These coordinates may refer either to a protein domain or to the entire tertiary structure. A number of these structures may bind to each other, forming a quaternary structure. History The science of the tertiary structure of proteins has progressed from one of hypothesis to one of detailed definition. Although Emil Fischer had suggested proteins were made of polypeptide chains and amino acid side chains, it was Dorothy Maud Wrinch who incorporated geometry into the prediction of protein structures. Wrinch demon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Enzymes
Enzymes are listed here by their classification in the International Union of Biochemistry and Molecular Biology's Enzyme Commission (EC) numbering system: :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-phoshitiendopene 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 disulfide as accep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus
''Bacillus'', from Latin "bacillus", meaning "little staff, wand", is a genus of Gram-positive, rod-shaped bacteria, a member of the phylum ''Bacillota'', with 266 named species. The term is also used to describe the shape (rod) of other so-shaped bacteria; and the plural ''Bacilli'' is the name of the class of bacteria to which this genus belongs. ''Bacillus'' species can be either obligate aerobes which are dependent on oxygen, or facultative anaerobes which can survive in the absence of oxygen. Cultured ''Bacillus'' species test positive for the enzyme catalase if oxygen has been used or is present. ''Bacillus'' can reduce themselves to oval endospores and can remain in this dormant state for years. The endospore of one species from Morocco is reported to have survived being heated to 420 °C. Endospore formation is usually triggered by a lack of nutrients: the bacterium divides within its cell wall, and one side then engulfs the other. They are not true spores (i.e. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isozyme
In biochemistry, isozymes (also known as isoenzymes or more generally as multiple forms of enzymes) are enzymes that differ in amino acid sequence but catalyze the same chemical reaction. Isozymes usually have different kinetic parameters (e.g. different ''K''M values), or are regulated differently. They permit the fine-tuning of metabolism to meet the particular needs of a given tissue or developmental stage. In many cases, isozymes are encoded by homologous genes that have diverged over time. Strictly speaking, enzymes with different amino acid sequences that catalyse the same reaction are isozymes if encoded by different genes, or allozymes if encoded by different alleles of the same gene; the two terms are often used interchangeably. Introduction Isozymes were first described by R. L. Hunter and Clement Markert (1957) who defined them as ''different variants of the same enzyme having identical functions and present in the same individual''. This definition encompasses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatic Sulfonation
In organic chemistry, aromatic sulfonation is a reaction in which a hydrogen atom on an arene is replaced by a sulfonic acid () group. Together with nitration and chlorination, aromatic sulfonation is a widely used electrophilic aromatic substitutions. Aryl sulfonic acids are used as detergents, dye, and drugs. : Stoichiometry and mechanism Typical conditions involve heating the aromatic compound with sulfuric acid: : Sulfur trioxide or its protonated derivative is the actual electrophile in this electrophilic aromatic substitution. To drive the equilibrium, dehydrating agents such as thionyl chloride can be added: : Historically, mercurous sulfate has been used to catalyze the reaction. Chlorosulfuric acid is also an effective agent: : In contrast to aromatic nitration and most other electrophilic aromatic substitutions this reaction is reversible. Sulfonation takes place in concentrated acidic conditions and desulfonation is the mode of action in a dilute hot aqueous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redox
Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. The oxidation and reduction processes occur simultaneously in the chemical reaction. There are two classes of redox reactions: * Electron transfer, Electron-transfer – Only one (usually) electron flows from the atom, ion, or molecule being oxidized to the atom, ion, or molecule that is reduced. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * Atom transfer – An atom transfers from one Substrate (chemistry), substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously, the oxidation state of oxygen decreases as it accepts electrons r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzoic Acid
Benzoic acid () is a white (or colorless) solid organic compound with the formula , whose structure consists of a benzene ring () with a carboxyl () substituent. The benzoyl group is often abbreviated "Bz" (not to be confused with "Bn," which is used for benzyl), thus benzoic acid is also denoted as BzOH, since the benzoyl group has the formula –. It is the simplest aromatic carboxylic acid. The name is derived from gum benzoin, which was for a long time its only source. Benzoic acid occurs naturally in many plants and serves as an intermediate in the biosynthesis of many secondary metabolites. Salts of benzoic acid are used as food preservatives. Benzoic acid is an important precursor for the industrial synthesis of many other organic substances. The salts and esters of benzoic acid are known as benzoates (). History Benzoic acid was discovered in the sixteenth century. The dry distillation of gum benzoin was first described by Nostradamus (1556), and then by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethylaniline
''N'',''N''-Dimethylaniline (DMA) is an organic chemical compound, a substituted derivative of aniline. It is a tertiary amine, featuring a dimethylamino group attached to a phenyl group. This oily liquid is colourless when pure, but commercial samples are often yellow. It is an important precursor to dyes such as crystal violet. Preparation DMA was first reported in 1850 by the German chemist A. W. Hofmann, who prepared it by heating aniline and iodomethane: :C6H5NH2 + 2 CH3I → C6H5N(CH3)2 + 2 HI DMA is produced industrially by alkylation of aniline with methanol in the presence of an acid catalyst:Kahl, Thomas ''et al.'' (2007) "Aniline" in ''Ullmann's Encyclopedia of Industrial Chemistry''. John Wiley & Sons: New York. :C6H5NH2 + 2 CH3OH → C6H5N(CH3)2 + 2 H2O Similarly, it is also prepared using dimethyl ether as the methylating agent. Reactions Dimethylaniline undergoes many of the reactions expected for an aniline, being weakly basic and reactive toward ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
