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Lichenase
Lichenase (, ''licheninase'', ''beta-(1->4)-D-glucan 4-glucanohydrolase'', ''1,3, 1,4-beta-glucan endohydrolase'', ''1,3, 1,4-beta-glucan 4-glucanohydrolase'', ''1,3-1,4-beta-D-glucan 4-glucanohydrolase'') is an enzyme with systematic name ''(1->3)-(1->4)-beta-D-glucan 4-glucanohydrolase''. It was named after its activity in on lichenin (a form of mixed-linkage glucan). Activity This enzyme catalyses the following chemical reaction :Hydrolysis of β-(1,4)-D-glucosidic linkages in mixed-linkage glucans containing both (1,3)- and (1,4)-bonds Specificity The best-characterised variant of this of enzyme is ''Bacillus subtilis ''Bacillus subtilis'', known also as the hay bacillus or grass bacillus, is a Gram-positive, catalase-positive bacterium, found in soil and the gastrointestinal tract of ruminants, humans and marine sponges. As a member of the genus ''Bacillus ...'' lichenase, which is used as a molecular biology tool in determining the structure of mixed-linkage gluc ... [...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 react ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichenin
Lichenin, also known as lichenan or moss starch, is a complex glucan occurring in certain species of lichens. It can be extracted from ''Cetraria islandica'' (Iceland moss). It has been studied since about 1957. Structure Chemically, lichenin is a mixed-linkage glucan, consisting of repeating glucose units linked by β-1,3 and β-1,4 glycosidic bonds. Uses It is an important carbohydrate for reindeers and northern flying squirrels, which eat the lichen '' Bryoria fremontii''. It can be extracted by digesting Iceland moss in a cold, weak solution of carbonate of soda for some time, and then boiling. By this process the lichenin is dissolved and on cooling separates as a colorless jelly. Iodine imparts no color to it. Other uses of the name In his 1960 novel ''Trouble with Lichen'', John Wyndham John Wyndham Parkes Lucas Beynon Harris (; 10 July 1903 – 11 March 1969) was an English science fiction writer best known for his works published under the pen name J ... [...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] |
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the substance and water molecule to split into two parts. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mixed-linkage Glucan
Mixed-linkage glucan (MLG), sometimes incorrectly referred to as beta-glucan, is a hemicellulosic polysaccharide consisting of β-D(1-3) and β-D(1-4) linked glucosyl residues. MLG is highly prevalent within the Poales, where it has important properties in the diet. In addition, although thought to be confined to the Poales, MLG has been found to be highly prevalent in plants of the distantly related genus ''Equisetum''. Structure MLG is composed of β-D(1-3) and β-D(1-4)-linked glucosyl residues. Typically there are regions of 2-5 β-D(1-4)-linked residues separated by β-D(1-3)-linkages. The β-D(1-4)-linked residues form rigid regions of the structure while the β-D(1-3)-links are flexible. Roles in the diet MLGs exhibit the physiological properties of dietary fibres and the functional properties of viscous and gel-forming food hydrocolloids.{{cite journal , doi=10.1016/j.jcs.2007.05.003 , last1=Lazaridou , first1=A. , last2=Biliaderis , first2=C.G. , year=2007 , title=M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Subtilis
''Bacillus subtilis'', known also as the hay bacillus or grass bacillus, is a Gram-positive, catalase-positive bacterium, found in soil and the gastrointestinal tract of ruminants, humans and marine sponges. As a member of the genus ''Bacillus'', ''B. subtilis'' is rod-shaped, and can form a tough, protective endospore, allowing it to tolerate extreme environmental conditions. ''B. subtilis'' has historically been classified as an obligate aerobe, though evidence exists that it is a facultative anaerobe. ''B. subtilis'' is considered the best studied Gram-positive bacterium and a model organism to study bacterial chromosome replication and cell differentiation. It is one of the bacterial champions in secreted enzyme production and used on an industrial scale by biotechnology companies. Description ''Bacillus subtilis'' is a Gram-positive bacterium, rod-shaped and catalase-positive. It was originally named ''Vibrio subtilis'' by Christian Gottfried Ehrenberg, and renamed ''Bacil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspergillus Japonicus
''Aspergillus violaceofuscus'' is a species of fungus in the genus ''Aspergillus''. It belongs to the group of black Aspergilli which are important industrial workhorses. ''A. violaceofuscus'' belongs to the ''Nigri'' section. The species was first described in 1887. It has been found both in marine environments in Bahamas and in soil in Puerto Rico.Varga, J.; Frisvad, J. C.; Kocsubé, S.; Brankovics, B.; Tóth, B.; Szigeti, G.; Samson, R. A. New and revisited species in Aspergillus section Nigri. Stud. Mycol. 2011, 69, 1–17, doi:10.3114/sim.2011.69.01. The genome of ''A. violaceofuscus'' was sequenced In genetics and biochemistry, sequencing means to determine the primary structure (sometimes incorrectly called the primary sequence) of an unbranched biopolymer. Sequencing results in a symbolic linear depiction known as a sequence which suc ... and published in 2014 as part of the ''Aspergillus'' whole-genome sequencing project – a project dedicated to performing whole-g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycoside Hydrolase Family 16
In molecular biology, Glycoside hydrolase family 16 is a family of glycoside hydrolases. Glycoside hydrolases are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycoside hydrolases, based on sequence similarity, has led to the definition of >100 different families. This classification is available on the CAZy CAZy is a database of Carbohydrate-Active enZYmes (CAZymes). The database contains a classification and associated information about enzymes involved in the synthesis, metabolism, and recognition of complex carbohydrates, i.e. disaccharides, olig ... web site, and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes. y _ Glycoside hydrolase family 1CAZY GH_16comprises enzymes with a number of known activities; lichenase (); xyloglucan xyloglucosyltransferase (); agarase (); kappa-carrageenase (); endo-beta- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jelly Roll Fold
The jelly roll or Swiss roll fold is a protein fold or supersecondary structure composed of eight beta strands arranged in two four-stranded sheets. The name of the structure was introduced by Jane S. Richardson in 1981, reflecting its resemblance to the jelly or Swiss roll cake. The fold is an elaboration on the Greek key motif and is sometimes considered a form of beta barrel. It is very common in viral proteins, particularly viral capsid proteins. Taken together, the jelly roll and Greek key structures comprise around 30% of the all-beta proteins annotated in the Structural Classification of Proteins (SCOP) database. Structure The basic jelly roll structure consists of eight beta strands arranged in two four-stranded antiparallel beta sheets which pack together across a hydrophobic interface here citation... uniprot The strands are traditionally labeled B through I for the historical reason that the first solved structure, of a jelly roll capsid protein from the toma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binding Site
In biochemistry and molecular biology, a binding site is a region on a macromolecule such as a protein that binds to another molecule with specificity. The binding partner of the macromolecule is often referred to as a ligand. Ligands may include other proteins (resulting in a protein-protein interaction), enzyme substrates, second messengers, hormones, or allosteric modulators. The binding event is often, but not always, accompanied by a conformational change that alters the protein's function. Binding to protein binding sites is most often reversible (transient and non-covalent), but can also be covalent reversible or irreversible. Function Binding of a ligand to a binding site on protein often triggers a change in conformation in the protein and results in altered cellular function. Hence binding site on protein are critical parts of signal transduction pathways. Types of ligands include neurotransmitters, toxins, neuropeptides, and steroid hormones. Binding sites incur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
