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Mucopolysaccharides
Glycosaminoglycans (GAGs) or mucopolysaccharides are long, linear polysaccharides consisting of repeating disaccharide units (i.e. two-sugar units). The repeating two-sugar unit consists of a uronic sugar and an amino sugar, except in the case of the sulfated glycosaminoglycan keratan, where, in place of the uronic sugar there is a galactose unit. GAGs are found in vertebrates, invertebrates and bacteria. Because GAGs are highly polar molecules and attract water; the body uses them as lubricants or shock absorbers. Mucopolysaccharidoses are a group of metabolic disorders in which abnormal accumulations of glycosaminoglycans occur due to enzyme deficiencies. Production Glycosaminoglycans vary greatly in molecular mass, disaccharide structure, and sulfation. This is because GAG synthesis is not template driven, as are proteins or nucleic acids, but constantly altered by processing enzymes. GAGs are classified into four groups, based on their core disaccharide structures. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mucopolysaccharidosis
Mucopolysaccharidoses are a group of metabolic disorders caused by the absence or malfunctioning of lysosomal enzymes needed to break down molecules called glycosaminoglycans (GAGs). These long chains of sugar carbohydrates occur within the cells that help build bone, cartilage, tendons, corneas, skin and connective tissue. GAGs (formerly called mucopolysaccharides) are also found in the fluids that lubricate joints. Individuals with mucopolysaccharidosis either do not produce enough of one of the eleven enzymes required to break down these sugar chains into simpler molecules, or they produce enzymes that do not work properly. Over time, these GAGs collect in the cells, blood and connective tissues. The result is permanent, progressive cellular damage which affects appearance, physical abilities, organ and system functioning. The mucopolysaccharidoses are part of the lysosomal storage disease family, a group of more than 40 genetic disorders that result when the lysosome o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratan Sulfate
Keratan sulfate (KS), also called keratosulfate, is any of several sulfated glycosaminoglycans (structural carbohydrates) that have been found especially in the cornea, cartilage, and bone. It is also synthesized in the central nervous system where it participates both in development and in the glial scar formation following an injury. Keratan sulfates are large, highly hydrated molecules which in joints can act as a cushion to absorb mechanical shock. Structure Like other glycosaminoglycans keratan sulfate is a linear polymer that consists of a repeating disaccharide unit. Keratan sulfate occurs as a proteoglycan (PG) in which KS chains are attached to cell-surface or extracellular matrix proteins, termed core proteins. KS core proteins include lumican, keratocan, mimecan, fibromodulin, PRELP, osteoadherin, and aggrecan. The basic repeating disaccharide unit within keratan sulfate is -3 Galβ1-4 GlcNAc6Sβ1-. This can be sulfated at carbon position 6 (C6) of either o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chondroitin Sulfate Structure NTP
A chondroitin is a chondrin derivative. Types include: * Chondroitin sulfate * Dermatan sulfate Chondroitin as a supplement is now commonly used (often in combination with glucosamine) in treating the joint disease of osteoarthritis. In contrast to the symptomatic treatments, chondroitin can modify the progression of a disease process in the patient which it can be used as an alternative medicine. Chondroitin's effect toward the articular cartilage integrity as it is part of the proteoglycan Proteoglycans are proteins that are heavily glycosylated. The basic proteoglycan unit consists of a "core protein" with one or more covalently attached glycosaminoglycan (GAG) chain(s). The point of attachment is a serine (Ser) residue to w ... molecules. The cartilage proteoglycan synthesis can speed up as chondroitin is going through the pathway of the alimentary canal. Research has been conducted to show the effectiveness of chondroitin and results indicate that it helps to manage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosyltransferase
Glycosyltransferases (GTFs, Gtfs) are enzymes (EC 2.4) that establish natural glycosidic linkages. They catalyze the transfer of saccharide moieties from an activated nucleotide sugar (also known as the " glycosyl donor") to a nucleophilic glycosyl acceptor molecule, the nucleophile of which can be oxygen- carbon-, nitrogen-, or sulfur-based. The result of glycosyl transfer can be a carbohydrate, glycoside, oligosaccharide, or a polysaccharide. Some glycosyltransferases catalyse transfer to inorganic phosphate or water. Glycosyl transfer can also occur to protein residues, usually to tyrosine, serine, or threonine to give O-linked glycoproteins, or to asparagine to give N-linked glycoproteins. Mannosyl groups may be transferred to tryptophan to generate C-mannosyl tryptophan, which is relatively abundant in eukaryotes. Transferases may also use lipids as an acceptor, forming glycolipids, and even use lipid-linked sugar phosphate donors, such as dolichol phosphates in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OGN (gene)
Osteoglycin (also called mimecan), encoded by the OGN gene, is a human protein. This gene encodes a protein which induces ectopic bone formation in conjunction with transforming growth factor beta. This protein is a small keratan sulfate proteoglycan which contains tandem leucine-rich repeats (LRR). The gene expresses three transcript variants. The level of expression of this gene has been correlated with enlarged hearts and more specifically left ventricular hypertrophy Left ventricular hypertrophy (LVH) is thickening of the heart muscle of the left ventricle of the heart, that is, left-sided ventricular hypertrophy and resulting increased left ventricular mass. Causes While ventricular hypertrophy occurs .... References Further reading * * * * * * * * * * * * * * * * * * * * {{proteoglycans Proteoglycans Extracellular matrix proteins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratocan
Keratocan (KTN) also known as keratan sulfate proteoglycan keratocan, is a protein that in humans is encoded by the ''KERA'' gene. Keratan sulfate proteoglycan Proteoglycans are proteins that are heavily glycosylated. The basic proteoglycan unit consists of a "core protein" with one or more covalently attached glycosaminoglycan (GAG) chain(s). The point of attachment is a serine (Ser) residue to whic ...s (KSPGs) are members of the small leucine-rich proteoglycan (SLRP) family. KSPGs, particularly keratocan, lumican and mimecan, are important to the transparency of the cornea. Mutations of the gene cause cornea plana 2. References Further reading * * * * * * * * * * * * * * * * {{gene-12-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumican
Lumican, also known as LUM, is an extracellular matrix protein that, in humans, is encoded by the ''LUM'' gene on chromosome 12. Structure Lumican is a proteoglycan Class II member of the small leucine-rich proteoglycan (SLRP) family that includes decorin, biglycan, fibromodulin, keratocan, epiphycan, and osteoglycin. Like the other SLRPs, lumican has a molecular weight of about 40 kiloDaltons and has four major intramolecular domains: #a signal peptide of 16 amino acid residues; #a negatively-charged N-terminal domain containing sulfated tyrosine and disulfide bond(s); #ten tandem leucine-rich repeats allowing lumican to bind to other extracellular components such as collagen; #a carboxyl terminal domain of 50 amino acid residues containing two conserved cysteines 32 residues apart. There are four N-linked sites within the leucine-rich repeat domain of the protein core that can be substituted with keratan sulfate. The core protein of lumican (like decorin and fibro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aggrecan
Aggrecan (ACAN), also known as cartilage-specific proteoglycan core protein (CSPCP) or chondroitin sulfate proteoglycan 1, is a protein that in humans is encoded by the ''ACAN'' gene. This gene is a member of the lectican ( chondroitin sulfate proteoglycan) family. The encoded protein is an integral part of the extracellular matrix in cartilagenous tissue and it withstands compression in cartilage. Aggrecan is a proteoglycan, or a protein modified with large carbohydrates; the human form of the protein is 2316 amino acids long and can be expressed in multiple isoforms due to alternative splicing. Aggrecan was named for its ability to form large aggregates in the cartilage tissue (a large aggregating proteoglycan). Structure Aggrecan is a high molecular weight (1x106 < M < 3x106) proteoglycan. It exhibits a bottlebrush structure, in which chondroitin sulfate and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heparan Sulfate 6-O-sulfotransferase
Heparan sulfate 6-sulfotransferases catalyses the transfer of sulfate from adenosine 3'-phosphate, 5'-phosphosulfate to the 6th position of the N- sulfoglucosamine residue in heparan sulfate Heparan sulfate (HS) is a linear polysaccharide found in all animal tissues. It occurs as a proteoglycan (HSPG, i.e. Heparan Sulfate ProteoGlycan) in which two or three HS chains are attached in close proximity to cell surface or extracellular m .... Human proteins containing this domain * HS6ST1 * HS6ST2 * HS6ST3 References {{DEFAULTSORT:Heparan Sulfate 6-O-Sulfotransferase EC 2.8.2 Protein domains Protein families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heparan Sulfate 2-O-sulfotransferase
Heparan sulfate 2-O-sulfotransferase is a sulfotransferase enzyme. Heparan sulfate (HS) is a long unbranched polysaccharide found covalently attached to various proteins at the cell surface and in the extracellular matrix, where it acts as a co-receptor for a number of growth factor A growth factor is a naturally occurring substance capable of stimulating cell proliferation, wound healing, and occasionally cellular differentiation. Usually it is a secreted protein or a steroid hormone. Growth factors are important for r ...s, morphogens, and adhesion proteins. HS-O-sulfotransferase (Hs2st) occupies a critical position in the succession of enzymes responsible for the biosynthesis of HS, catalysing the transfer of sulfate to the C2-position of selected hexuronic acid residues within the nascent HS chain. Mice that lack HS2ST undergo developmental failure after midgestation, the most dramatic effect being the complete failure of kidney development. This family is related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NDST1
Bifunctional heparan sulfate N-deacetylase/N-sulfotransferase 1 is an enzyme. In humans, it is encoded by the ''NDST1'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba .... References Further reading * * * * * * * * * * Human proteins {{gene-5-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
