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Mannans
Mannans are polymers containing the sugar mannose as a principal component. They are a type of polysaccharide comprise hemicellulose, a major source of biomass found in higher plants such as softwoods. These polymers also typically contain two other sugars, galactose and glucose. They are often branched (unlike cellulose). Structural diversity Plant mannans have β(1-4) linkages, occasionally with α(1-6) galactose branches, forming galactomannans. They are insoluble and a form of storage polysaccharide. Ivory nut is a source of mannans. An additional type is galactoglucomannan found in soft wood with a mixed mannose/glucose β(1-4) backbone. Many mannans are acetylated and some from marine sources, have sulfate esters side chains. Yeast and some plants such as conjac and salep have a different type of mannans in their cell wall, with a α(1-6) linked backbone and α(1-2) and α(1-3) linked glucose branches, hence "glucomannan". It is water soluble. It is serologically simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucomannan
Glucomannan is a water-soluble polysaccharide that is considered a dietary fiber. It is a hemicellulose component in the cell walls of some plant species. Glucomannan is a food additive used as an emulsifier and thickener. It is a major source of mannan oligosaccharide (MOS) found in nature, the other being galactomannan, which is insoluble. Products containing glucomannan, under a variety of brand names, are marketed as dietary supplements with claims they can relieve constipation and help lower cholesterol levels. Since 2010 they are legally marketed in Europe as helping with weight loss for people who are overweight and eating a diet with restricted calories, but there was no good evidence that glucomannan helped weight loss. Supplements containing glucomannans pose a risk for choking and bowel obstruction if they are not taken with sufficient water. Other adverse effects include diarrhea, belching, and bloating; in one study people taking glucomannans had higher triglyce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucomannan
Glucomannan is a water-soluble polysaccharide that is considered a dietary fiber. It is a hemicellulose component in the cell walls of some plant species. Glucomannan is a food additive used as an emulsifier and thickener. It is a major source of mannan oligosaccharide (MOS) found in nature, the other being galactomannan, which is insoluble. Products containing glucomannan, under a variety of brand names, are marketed as dietary supplements with claims they can relieve constipation and help lower cholesterol levels. Since 2010 they are legally marketed in Europe as helping with weight loss for people who are overweight and eating a diet with restricted calories, but there was no good evidence that glucomannan helped weight loss. Supplements containing glucomannans pose a risk for choking and bowel obstruction if they are not taken with sufficient water. Other adverse effects include diarrhea, belching, and bloating; in one study people taking glucomannans had higher triglyce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galactomannan
Galactomannans are polysaccharides consisting of a mannose backbone with galactose side groups, more specifically, a (1-4)-linked beta-D-mannopyranose backbone with branchpoints from their 6-positions linked to alpha-D-galactose, (i.e. 1-6-linked alpha-D-galactopyranose). In order of increasing number of mannose-to-galactose ratio: *fenugreek, fenugreek gum, mannose:galactose ~1:1 *guar gum, mannose:galactose ~2:1 *tara gum, mannose:galactose ~3:1 *locust bean gum or ''carob gum'', mannose:galactose ~4:1 *cassia gum, mannose:galactose ~5:1 Galactomannans are often used in food products to increase the viscosity of the water phase. Guar gum has been used to add viscosity to artificial tears, but is not as stable as Carboxymethyl cellulose, carboxymethylcellulose. Food use Galactomannans are used in foods as stabilizer (chemistry), stabilisers. Guar and locust bean gum (LBG) are commonly used in ice cream to improve texture and reduce ice cream meltdown. LBG is also used extensiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galactoglucomannan
Galactoglucomannan is a water-soluble hemicellulose, consisting of galactose, glucose and mannose. Many softwood species, e.g. Norway spruce are rich of galactoglucomannans and can contain it up to 10–20%. Structure Galactoglucomannan consists of a backbone of randomly distributed (1→4)-linked mannose and glucose units with (1→6)-linked galactose units attached to mannose units. The hydroxyl In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydro ... groups in locations C2 and C3 in mannose are partially substituted by acetyl groups. References Polysaccharides {{Polymer-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannose
Mannose is a sugar monomer of the aldohexose series of carbohydrates. It is a C-2 epimer of glucose. Mannose is important in human metabolism, especially in the glycosylation of certain proteins. Several congenital disorders of glycosylation are associated with mutations in enzymes involved in mannose metabolism. Mannose is not an essential nutrient; it can be produced in the human body from glucose, or converted into glucose. Mannose provides 2–5 kcal/g. It is partially excreted in the urine. Etymology The root of both "mannose" and "mannitol" is manna, which the Bible describes as the food supplied to the Israelites during their journey in the region of Sinai. Several trees and shrubs can produce a substance called manna, such as the "manna tree" ('' Fraxinus ornus'') from whose secretions mannitol was originally isolated. Structure Mannose commonly exists as two different-sized rings, the pyranose (six-membered) form and the furanose (five-membered) form. Eac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannan With Galactose Side Chain
Mannan may refer to: * Mannan (polysaccharide), a type of carbohydrate * Mannan people, a social group of India * Mannan language, a language of India * ''Mannan'' (film), a 1992 Indian film * Manannán, known in Manx as ''Mannan'', a figure in Gaelic mythology People with the name * Mannan Hira (1956–2020), Bangladeshi dramatist and filmmaker * Khandaker Abdul Mannan, Bangladesh Freedom Party politician and the former Member of Parliament * Gazi Alimuddin Mannan (1930–1990), Bangladeshi dancer and choreographer * Hasina Mannan (born 1947), Bangladesh Awami League politician and the former Member of Parliament * M. A. Mannan, Bangladesh Nationalist Party politician, first mayor of Gazipur City Corporation and former religious affairs minister * M. Sam Mannan (1954–2018), American chemical engineer * Masud Mannan (born 1961), Bangladeshi diplomat * Muhammad Abdul Mannan (born 1946), Bangladeshi politician, diplomat and bureaucrat and the incumbent Minister of Planni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucosidase
Glucosidases are the glycoside hydrolase enzymes categorized under the EC number 3.2.1. Function Alpha-glucosidases are enzymes involved in breaking down complex carbohydrates such as starch and glycogen into their monomers. They catalyze the cleavage of individual glucosyl residues from various glycoconjugates including alpha- or beta-linked polymers of glucose. This enzyme convert complex sugars into simpler ones. Members Different sources include different members in this class. Members marked with a "#" are considered by MeSH A mesh is a barrier made of connected strands of metal, fiber, or other flexible or ductile materials. A mesh is similar to a web or a net in that it has many attached or woven strands. Types * A plastic mesh may be extruded, oriented, exp ... to be glucosidases. Clinical significance Alpha-glucosidases are targeted by alpha-glucosidase inhibitors such as acarbose and miglitol to control diabetes mellitus type 2. See also * DNA gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannose-6-phosphate
Mannose-6-phosphate (M6P) is a molecule bound by lectin in the immune system. M6P is converted to fructose 6-phosphate by mannose phosphate isomerase. M6P is a key targeting signal for acid hydrolase precursor proteins that are destined for transport to lysosomes. The M6P tag is added to such proteins in the ''cis''-Golgi apparatus. Specifically, in a reaction involving uridine diphosphate (UDP) and ''N''-acetylglucosamine, the enzyme N-acetylglucosamine-1-phosphate transferase catalyzes the ''N''-linked glycosylation of asparagine residues with M6P. Once appropriately marked with the M6P targeting signal, these proteins are moved to the ''trans''-Golgi network. There, the M6P moiety is recognized and bound by mannose 6-phosphate receptor (MPR) proteins at pH 6.5–6.7. The M6P-tagged lysosomal enzymes are shipped to the late endosomes via vesicular transport. Enzyme replacement therapy (ERT) for several lysosomal storage diseases relies on this pathway to efficiently direct syn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannose-1-phosphate Guanylyltransferase
In enzymology, a mannose-1-phosphate guanylyltransferase () is an enzyme that catalyzes the chemical reaction :GTP + alpha-D-mannose 1-phosphate \rightleftharpoons diphosphate + GDP-mannose Thus, the two substrates of this enzyme are GTP and alpha-D-mannose 1-phosphate, whereas its two products are diphosphate and GDP-mannose. This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing nucleotide groups (nucleotidyltransferases). The systematic name of this enzyme class is GTP:alpha-D-mannose-1-phosphate guanylyltransferase. Other names in common use include GTP-mannose-1-phosphate guanylyltransferase, PIM-GMP (phosphomannose isomerase-guanosine 5'-diphospho-D-mannose, pyrophosphorylase), GDP-mannose pyrophosphorylase, guanosine 5'-diphospho-D-mannose pyrophosphorylase, guanosine diphosphomannose pyrophosphorylase, guanosine triphosphate-mannose 1-phosphate guanylyltransferase, and mannose 1-phosphate guanylyltransferase (guanosine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannosidase
Mannosidase is an enzyme which hydrolyses mannose. There are two types: * alpha-Mannosidase * beta-Mannosidase Beta-mannosidase (, ''mannanase'', ''mannase'', ''beta-D-mannosidase'', ''beta-mannoside mannohydrolase'', ''exo-beta-D-mannanase'', ''lysosomal beta A mannosidase'') is an enzyme with List of enzymes, systematic name ''beta-D-mannoside mannoh ... A deficiency is associated with mannosidosis. A family of mannosidases are also responsible for processing newly formed glycoproteins in the endoplasmic reticulum into mature glycoproteins containing highly heterogeneous complex-type glycans. References EC 3.2.1 {{3.2-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esterase
An esterase is a hydrolase enzyme that splits esters into an acid and an alcohol in a chemical reaction with water called hydrolysis. A wide range of different esterases exist that differ in their substrate specificity, their protein structure, and their biological function. EC classification/list of enzymes * ''EC 3.1.1'': Carboxylic ester hydrolases ** Acetylesterase (EC 3.1.1.6), splits off acetyl groups *** Cholinesterase **** Acetylcholinesterase, inactivates the neurotransmitter acetylcholine **** Pseudocholinesterase, broad substrate specificity, found in the blood plasma and in the liver ** Pectinesterase (EC 3.1.1.11), clarifies fruit juices * ''EC 3.1.2'': Thiolester hydrolases ** Thioesterase *** Ubiquitin carboxy-terminal hydrolase L1 * ''EC 3.1.3'': Phosphoric monoester hydrolases ** Phosphatase (EC 3.1.3.x), hydrolyses phosphoric acid monoesters into a phosphate ion and an alcohol *** Alkaline phosphatase, removes phosphate groups from many types of molecules, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannase
Beta-mannosidase (, ''mannanase'', ''mannase'', ''beta-D-mannosidase'', ''beta-mannoside mannohydrolase'', ''exo-beta-D-mannanase'', ''lysosomal beta A mannosidase'') is an enzyme with systematic name ''beta-D-mannoside mannohydrolase'', which is in humans encoded by the ''MANBA'' gene. This enzyme catalyses the following 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 pos ... : Hydrolysis of terminal, non-reducing beta-D-mannose residues in beta-D-mannosides This gene encodes a member of the glycosyl hydrolase 2 family. The encoded protein localizes to the lysosome where it is the final exoglycosidase in the pathway for N-linked glycoprotein oligosaccharide catabolism. Mutations in this gene are associated with beta-mannosidosis, a lysosomal storage disease that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
