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5-phytase
The enzyme 5-phytase (EC 3.1.3.72) catalyzes the reaction :''myo''-inositol hexakisphosphate + H2O = 1L-''myo''-inositol 1,2,3,4,6-pentakisphosphate + phosphate ''myo''-Inositol hexakisphosphate is also known as phytic acid. These enzymes belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name of this enzyme class is ''myo''-inositol-hexakisphosphate 5-phosphohydrolase. Prevalence Of the hundreds of phytase enzymes that have been characterized in the literature, only two have been characterized as 5-phytases. A histidine acid phosphatases purified from lily pollen and a protein tyrosine phosphatase-like phytase from ''Selenomonas ruminantium'' subsp. ''lactilytica'' were both found to have specificity for the 5-phosphate position of ''myo''-inositol hexakisphosphate. Structural studies As of late 2007, only the phytase purified from lily pollen had its structure solved, with PDB accession codes , , , , , and . See a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4-phytase
The enzyme 4-phytase () catalyzes the following reaction: : ''myo''-inositol hexakisphosphate + H2O \rightleftharpoons 1D-''myo''-inositol 1,2,3,5,6-pentakisphosphate + phosphate ''myo''-Inositol hexakisphosphate is also known as phytic acid. These enzymes belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name of this enzyme class is ''myo''-inositol-hexakisphosphate 4-phosphohydrolase. Other names in common use include 6-phytase (name based on 1 L-numbering system and not 1D-numbering) and phytate 6-phosphatase. Enzymes of this type participate in inositol phosphate metabolism. See also * 3-phytase (1-phytase) * 5-phytase * Protein tyrosine phosphatase Protein tyrosine phosphatases (EC 3.1.3.48, systematic name protein-tyrosine-phosphate phosphohydrolase) are a group of enzymes that remove phosphate groups from phosphorylated tyrosine residues on proteins: : proteintyrosine phosphate + H2O = ... References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-phytase
The enzyme 3-phytase (EC 3.1.3.8) catalyzes the reaction : ''myo''-inositol hexakisphosphate + H2O = 1D-''myo''-inositol 1,2,4,5,6-pentakisphosphate + phosphate ''myo''-Inositol hexakisphosphate is also known as phytic acid. These enzymes belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name ''myo''-inositol-hexakisphosphate 3-phosphohydrolase. Other names in common use include 1-phytase, phytate 1-phosphatase, phytate 3-phosphatase, and phytate 6-phosphatase. Enzymes of this type participate in inositol phosphate metabolism. Structural studies As of late 2007, 12 structures have been solved for this class of enzymes, with PDB accession codes , , , , , , , , , , , and . See also * 4-phytase (6-phytase) * 5-phytase * Protein tyrosine phosphatase Protein tyrosine phosphatases (EC 3.1.3.48, systematic name protein-tyrosine-phosphate phosphohydrolase) are a group of enzymes that remove phosphate groups from phospho ... [...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] |
Phytic Acid
Phytic acid is a six-fold dihydrogenphosphate ester of inositol (specifically, of the ''myo'' isomer), also called inositol hexakisphosphate (IP6) or inositol polyphosphate. At physiological pH, the phosphates are partially ionized, resulting in the phytate anion. The (''myo'') phytate anion is a colorless species that has significant nutritional role as the principal storage form of phosphorus in many plant tissues, especially bran and seeds. It is also present in many legumes, cereals, and grains. Phytic acid and phytate have a strong binding affinity to the dietary minerals, calcium, iron, and zinc, inhibiting their absorption in the small intestine. The lower inositol polyphosphates are inositol esters with less than six phosphates, such as inositol penta- (IP5), tetra- (IP4), and triphosphate (IP3). These occur in nature as catabolites of phytic acid. Significance in agriculture Phytic acid was discovered in 1903. Generally, phosphorus and inositol in phytate form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolase
Hydrolase is a class of enzyme that commonly perform as biochemical catalysts that use water to break a chemical bond, which typically results in dividing a larger molecule into smaller molecules. Some common examples of hydrolase enzymes are esterases including lipases, phosphatases, glycosidases, peptidases, and nucleosidases. Esterases cleave ester bonds in lipids and phosphatases cleave phosphate groups off molecules. An example of crucial esterase is acetylcholine esterase, which assists in transforming the neuron impulse into the acetate group after the hydrolase breaks the acetylcholine into choline and acetic acid. Acetic acid is an important metabolite in the body and a critical intermediate for other reactions such as glycolysis. Lipases hydrolyze glycerides. Glycosidases cleave sugar molecules off carbohydrates and peptidases hydrolyze peptide bonds. Nucleosidases hydrolyze the bonds of nucleotides. Hydrolase enzymes are important for the body because they have degra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ester
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. They perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties. '' Nomenclature Etymology Th ... [...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] |
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 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.Branden C. and Tooze J. "Introduction to Protein Structure" Garland Publishing, New York. 1990 and 1991. A number of tertiary structures may fold into a quaternary structure.Kyte, J. "Structure in Protein Chemistry." Garland Publishing, New York. 1995. 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 polypept ... [...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. The data, typically obtained by X-ray crystallography, NMR spectroscopy, or, increasingly, cryo-electron microscopy, and submitted by biologists and biochemists from around the world, are freely accessible on the Internet via the websites of its member organisations (PDBe, PDBj, RCSB, and BMRB). The PDB is overseen by an organization called the Worldwide Protein Data Bank, wwPDB. 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 databases use protein structures deposited in the PDB. For example, SCOP and CATH classify protein structures, while PDBsum provides a graphic overview of PDB entries using information from other sources, such as Gene ontology. History Two force ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Tyrosine Phosphatase
Protein tyrosine phosphatases (EC 3.1.3.48, systematic name protein-tyrosine-phosphate phosphohydrolase) are a group of enzymes that remove phosphate groups from phosphorylated tyrosine residues on proteins: : proteintyrosine phosphate + H2O = proteintyrosine + phosphate Protein tyrosine (pTyr) phosphorylation is a common post-translational modification that can create novel recognition motifs for protein interactions and cellular localization, affect protein stability, and regulate enzyme activity. As a consequence, maintaining an appropriate level of protein tyrosine phosphorylation is essential for many cellular functions. Tyrosine-specific protein phosphatases (PTPase; ) catalyse the removal of a phosphate group attached to a tyrosine residue, using a cysteinyl-phosphate enzyme intermediate. These enzymes are key regulatory components in signal transduction pathways (such as the MAP kinase pathway) and cell cycle control, and are important in the control of cell growth, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
