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Class I Chitinase
Chitinases (EC 3.2.1.14, chitodextrinase, 1,4-β-poly-N-acetylglucosaminidase, poly-β-glucosaminidase, β-1,4-poly-N-acetyl glucosamidinase, poly ,4-(N-acetyl-β-D-glucosaminide)glycanohydrolase, (1→4)-2-acetamido-2-deoxy-β-D-glucan glycanohydrolase; systematic name (1→4)-2-acetamido-2-deoxy-β-D-glucan glycanohydrolase) are hydrolytic enzymes that break down glycosidic bonds in chitin. They catalyse the following reaction: : Random endo-hydrolysis of ''N''-acetyl-β-D-glucosaminide (1→4)-β-linkages in chitin and chitodextrins As chitin is a component of the cell walls of fungi and exoskeletal elements of some animals (including mollusks and arthropods), chitinases are generally found in organisms that either need to reshape their own chitin or dissolve and digest the chitin of fungi or animals. Species distribution Chitinivorous organisms include many bacteria ( Aeromonads, ''Bacillus'', ''Vibrio'', among others), which may be pathogenic or detritivorous. They a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Class I Chitinase
Chitinases (EC 3.2.1.14, chitodextrinase, 1,4-β-poly-N-acetylglucosaminidase, poly-β-glucosaminidase, β-1,4-poly-N-acetyl glucosamidinase, poly ,4-(N-acetyl-β-D-glucosaminide)glycanohydrolase, (1→4)-2-acetamido-2-deoxy-β-D-glucan glycanohydrolase; systematic name (1→4)-2-acetamido-2-deoxy-β-D-glucan glycanohydrolase) are hydrolytic enzymes that break down glycosidic bonds in chitin. They catalyse the following reaction: : Random endo-hydrolysis of ''N''-acetyl-β-D-glucosaminide (1→4)-β-linkages in chitin and chitodextrins As chitin is a component of the cell walls of fungi and exoskeletal elements of some animals (including mollusks and arthropods), chitinases are generally found in organisms that either need to reshape their own chitin or dissolve and digest the chitin of fungi or animals. Species distribution Chitinivorous organisms include many bacteria ( Aeromonads, ''Bacillus'', ''Vibrio'', among others), which may be pathogenic or detritivorous. They a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multimer
In chemistry and biochemistry, an oligomer () is a molecule that consists of a few repeating units which could be derived, actually or conceptually, from smaller molecules, monomer, monomers.Quote: ''Oligomer molecule: A molecule of intermediate relative molecular mass, the structure of which essentially comprises a small plurality of units derived, actually or conceptually, from molecules of lower relative molecular mass.'' The name is composed of Greek language, Greek elements ''wikt:oligo-, oligo-'', "a few" and ''wikt:-mer, -mer'', "parts". An adjective form is ''oligomeric''. The oligomer concept is contrasted to that of a polymer, which is usually understood to have a large number of units, possibly thousands or millions. However, there is no sharp distinction between these two concepts. One proposed criterion is whether the molecule's properties vary significantly with the removal of one or a few of the units. An oligomer with a specific number of units is referred t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CHI3L1
Chitinase-3-like protein 1 (CHI3L1), also known as YKL-40, is a secreted glycoprotein that is approximately 40k Da in size that in humans is encoded by the ''CHI3L1'' gene. The name YKL-40 is derived from the three N-terminal amino acids present on the secreted form and its molecular mass. YKL-40 is expressed and secreted by various cell-types including macrophages, chondrocytes, fibroblast-like synovial cells, vascular smooth muscle cells, and hepatic stellate cells. The biological function of YKL-40 is unclear. It is not known to have a specific receptor. Its pattern of expression is associated with pathogenic processes related to inflammation, extracellular tissue remodeling, fibrosis and solid carcinomas and asthma. Function Chitinases catalyze the hydrolysis of chitin, which is an abundant glycopolymer found in insect exoskeletons and fungal cell walls. The glycoside hydrolase 18 family of chitinases includes eight human family members. This gene encodes a glycoprotein me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme Induction And Inhibition
Enzyme induction is a process in which a molecule (''e.g.'' a drug) induces (''i.e.'' initiates or enhances) the expression of an enzyme. Enzyme inhibition can refer to * the inhibition of the expression of the enzyme by another molecule * interference at the enzyme-level, basically with how the enzyme works. This can be competitive inhibition, uncompetitive inhibition, non-competitive inhibition or partially competitive inhibition. If the molecule induces enzymes that are responsible for its own metabolism, this is called auto-induction (or auto-inhibition if there is inhibition). These processes are particular forms of gene expression regulation. These terms are of particular interest to pharmacology, and more specifically to drug metabolism and drug interactions. They also apply to molecular biology. History In the late 1950s and early 1960s, the French molecular biologists François Jacob and Jacques Monod became the first to explain enzyme induction, in the context of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogenesis Related (PR) Proteins
Pathogenesis-related (PR) proteins are proteins produced in plants in the event of a pathogen attack. They are induced as part of systemic acquired resistance. Infections activate genes that produce PR proteins. Some of these proteins are antimicrobial, attacking molecules in the cell wall of a bacterium or fungus. Others may function as signals that spread “news” of the infection to nearby cells. Infections also stimulate the cross-linking of molecules in the cell wall and the deposition of lignin, responses that set up a local barricade that slows spread of the pathogen to other parts of the plant. Salicylic acid plays a role in the resistance to pathogens by inducing the production of pathogenesis-related proteins. Many proteins found in wine are grape pathogen-related proteins. Those include thaumatin-like proteins and chitinases. Many pathogenesis-related protein families also coincide with groups of human allergens, even though the allergy may have nothing to do with th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Powdery Mildew Of Barley
Powdery mildew is a fungal disease of barley caused by ''Blumeria graminis'' f. sp. ''hordei''. The disease has a worldwide distribution and is most damaging in cool, wet climates. The host range of the form species ''hordei'' is restricted to barley and other ''Hordeum species''. Symptoms At first, powdery mildew can be observed as small greyish patches of fluffy fungal growth (mycelium) on the upper surface of the lower leaves. These spots resemble small cushions of white powder. Leaf tissue on the opposite side of an infected leaf turns pale green to yellow. The fungus only infects the epidermal layer and can be easily scraped off with a fingernail. Infections can also occur on the leaf sheaths and ears. Leaves remain green and active for some time following infection, then gradually become chlorotic and die off. As the disease progresses, the mycelium often becomes dotted with minute black points (cleistothecia), which are the sexual fruiting bodies of the fungus. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
β-1,3-glucanase
Glucanases are enzymes that break down large polysaccharides via hydrolysis. The product of the hydrolysis reaction is called a glucan, a linear polysaccharide made of up to 1200 glucose monomers, held together with glycosidic bonds. Glucans are abundant in the endosperm cell walls of cereals such as barley, rye, sorghum, rice, and wheat. Glucanases are also referred to as lichenases, hydrolases, glycosidases, glycosyl hydrolases, and/or laminarinases. Many types of glucanases share similar amino acid sequences but vastly different substrates. Of the known endo-glucanases, 1,3-1,4-β-glucanase is considered the most active. Structure β-glucanases The secondary and tertiary structures of β-glucanases involves the stacking of multiple β-sheets, each of which are made of several anti-parallel strands that bend and form a cleft crossing the active site of the enzyme. This type of structure has been called the "jelly roll fold." Some common β-glucanases * 1,3-β-glucanas ... [...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 (1) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Chemical Society
The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 155,000 members at all degree levels and in all fields of chemistry, chemical engineering, and related fields. It is one of the world's largest scientific societies by membership. The ACS is a 501(c) organization, 501(c)(3) non-profit organization and holds a congressional charter under Title 36 of the United States Code. Its headquarters are located in Washington, D.C., and it has a large concentration of staff in Columbus, Ohio. The ACS is a leading source of scientific information through its peer-reviewed scientific journals, national conferences, and the Chemical Abstracts Service. Its publications division produces over 60 Scientific journal, scholarly journals including the prestigious ''Journal of the American Chemical Society'', as well as the weekly tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambridge University Press
Cambridge University Press is the university press of the University of Cambridge. Granted letters patent by Henry VIII of England, King Henry VIII in 1534, it is the oldest university press A university press is an academic publishing house specializing in monographs and scholarly journals. Most are nonprofit organizations and an integral component of a large research university. They publish work that has been reviewed by schola ... in the world. It is also the King's Printer. Cambridge University Press is a department of the University of Cambridge and is both an academic and educational publisher. It became part of Cambridge University Press & Assessment, following a merger with Cambridge Assessment in 2021. With a global sales presence, publishing hubs, and offices in more than 40 Country, countries, it publishes over 50,000 titles by authors from over 100 countries. Its publishing includes more than 380 academic journals, monographs, reference works, school and uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seed Science Research
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosperm plants. Seeds are the product of the ripened ovule, after the embryo sac is fertilized by sperm from pollen, forming a zygote. The embryo within a seed develops from the zygote, and grows within the mother plant to a certain size before growth is halted. The seed coat arises from the integuments of the ovule. Seeds have been an important development in the reproduction and success of vegetable gymnosperm and angiosperm plants, relative to more primitive plants such as ferns, mosses and liverworts, which do not have seeds and use water-dependent means to propagate themselves. Seed plants now dominate biological niches on land, from forests to grasslands both in hot and cold climates. The term "seed" also has a general meaning that antedat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
