chondroitin-glucuronate 5-epimerase | |||||||||
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Identifiers | |||||||||
EC no. | 5.1.3.19 | ||||||||
CAS no. | 86417-91-6 | ||||||||
Databases | |||||||||
IntEnz | IntEnz view | ||||||||
BRENDA | BRENDA entry | ||||||||
ExPASy | NiceZyme view | ||||||||
KEGG | KEGG entry | ||||||||
MetaCyc | metabolic pathway | ||||||||
PRIAM | profile | ||||||||
PDB structures | RCSB PDB PDBe PDBsum | ||||||||
Gene Ontology | AmiGO / QuickGO | ||||||||
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In enzymology, a chondroitin-glucuronate 5-epimerase (EC 5.1.3.19) is an enzyme that catalyzes the chemical reaction
Hence, this enzyme has one substrate, chondroitin D-glucuronate, and one product, dermatan L-iduronate.
This enzyme belongs to the family of isomerases, specifically those racemases and epimerases acting on carbohydrates and derivatives. The systematic name of this enzyme class is chondroitin-D-glucuronate 5-epimerase. Other names in common use include polyglucuronate 5-epimerase, dermatan-sulfate 5-epimerase, urunosyl C-5 epimerase, and chondroitin D-glucuronosyl 5-epimerase. This enzyme participates in chondroitin sulfate biosynthesis.
Chondroitin sulfate is a sulfated glycosaminoglycan (GAG) composed of a chain of alternating sugars. It is usually found attached to proteins as part of a proteoglycan. A chondroitin chain can have over 100 individual sugars, each of which can be sulfated in variable positions and quantities. Chondroitin sulfate is an important structural component of cartilage, and provides much of its resistance to compression. Along with glucosamine, chondroitin sulfate has become a widely used dietary supplement for treatment of osteoarthritis, although large clinical trials failed to demonstrate any symptomatic benefit of chondroitin.
Glycosaminoglycans (GAGs) or mucopolysaccharides are long, linear polysaccharides consisting of repeating disaccharide 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.
Glucuronic acid is a uronic acid that was first isolated from urine. It is found in many gums such as gum arabic, xanthan, and kombucha tea and is important for the metabolism of microorganisms, plants and animals.
Heparan sulfate (HS) is a linear polysaccharide found in all animal tissues. It occurs as a proteoglycan in which two or three HS chains are attached in close proximity to cell surface or extracellular matrix proteins. In this form, HS binds to a variety of protein ligands, including Wnt, and regulates a wide range of biological activities, including developmental processes, angiogenesis, blood coagulation, abolishing detachment activity by GrB, and tumour metastasis. HS has also been shown to serve as cellular receptor for a number of viruses, including the respiratory syncytial virus. One study suggests that cellular heparan sulfate has a role in SARS-CoV-2 Infection, particularly when the virus attaches with ACE2.
Sulfatases EC 3.1.6.- are enzymes of the esterase class that catalyze the hydrolysis of sulfate esters. These may be found on a range of substrates, including steroids, carbohydrates and proteins. Sulfate esters may be formed from various alcohols and amines. In the latter case the resultant N-sulfates can also be termed sulfamates.
Arylsulfatase B is an enzyme associated with mucopolysaccharidosis VI.
Heparosan-N-sulfate-glucuronate 5-epimerase is an enzyme with systematic name poly( -beta-D-glucuronosyl- -N-sulfo-alpha-D-glucosaminyl) glucurono-5-epimerase. This enzyme catalyses the following chemical reaction
In enzymology, an UDP-glucuronate 5'-epimerase is an enzyme that catalyzes the chemical reaction
The enzyme chondroitin B lyase catalyzes the following process:
The enzyme heparin lyase catalyzes the following process:
In enzymology, a galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a galactosylxylosylprotein 3-beta-galactosyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a N-acetylgalactosaminyl-proteoglycan 3-beta-glucuronosyltransferase is an enzyme that catalyzes the chemical reaction
Xylosyltransferase 2 is an enzyme that in humans is encoded by the XYLT2 gene.
Dermatan-sulfate epimerase is an enzyme that in humans is encoded by the DSE gene.
Carbohydrate sulfotransferase 12 is an enzyme that in humans is encoded by the CHST12 gene.
Carbohydrate sulfotransferase 14 is an enzyme that in humans is encoded by the CHST14 gene.
Glucuronylgalactosylproteoglycan 4-beta-N-acetylgalactosaminyltransferase is an enzyme with systematic name UDP-N-acetyl-D-galactosamine:D-glucuronyl-(1->3)-beta-D-galactosyl-proteoglycan 4-beta-N-acetylgalactosaminyltransferase. This enzyme catalyses the following chemical reaction
N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase is an enzyme with systematic name 3'-phosphoadenylyl-sulfate:(dermatan)-4-O-sulfo-N-acetyl-D-galactosamine 6-O-sulfotransferase. This enzyme catalyses the following chemical reaction
Dermatan 4-sulfotransferase is an enzyme with systematic name 3'-phospho-5'-adenylyl sulfate:(dermatan)-N-acetyl-D-galactosamine 4-sulfotransferase. This enzyme catalyses the following chemical reaction