|
Sulfatase
Sulfatases 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. Sulfatases play important roles in the cycling of sulfur in the environment, in the degradation of sulfated glycosaminoglycans and glycolipids in the lysosome, and in remodelling sulfated glycosaminoglycans in the extracellular space. Together with sulfotransferases, sulfatases form the major catalytic machinery for the synthesis and breakage of sulfate esters. Occurrence and importance Sulfatases are found in lower and higher organisms. In higher organisms they are found in intracellular and extracellular spaces. Steroid sulfatase is distributed in a wide range of tissues throughout the body, enabling sulfated steroids synthesized in the adrenals and gonads ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroid Sulfatase
Steroid sulfatase (STS), or steryl-sulfatase (EC 3.1.6.2), formerly known as arylsulfatase C, is a sulfatase enzyme involved in the metabolism of steroids. It is encoded by the ''STS'' gene. Reactions This enzyme catalyses the following chemical reaction : 3β-hydroxyandrost-5-en-17-one 3-sulfate + H2O \rightleftharpoons 3β-hydroxyandrost-5-en-17-one + sulfate Also acts on some related steryl sulfates. Function The protein encoded by this gene catalyzes the conversion of sulfated steroid precursors to the free steroid. This includes DHEA sulfate, estrone sulfate, pregnenolone sulfate, and cholesterol sulfate, all to their unconjugated forms (DHEA, estrone, pregnenolone, and cholesterol, respectively). The encoded protein is found in the endoplasmic reticulum, where it is present as a homodimer. Clinical significance A congenital deficiency in the enzyme is associated with X-linked ichthyosis, a scaly-skin disease affecting roughly 1 in every 2,000 to 6,000 males. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroid Sulfatase
Steroid sulfatase (STS), or steryl-sulfatase (EC 3.1.6.2), formerly known as arylsulfatase C, is a sulfatase enzyme involved in the metabolism of steroids. It is encoded by the ''STS'' gene. Reactions This enzyme catalyses the following chemical reaction : 3β-hydroxyandrost-5-en-17-one 3-sulfate + H2O \rightleftharpoons 3β-hydroxyandrost-5-en-17-one + sulfate Also acts on some related steryl sulfates. Function The protein encoded by this gene catalyzes the conversion of sulfated steroid precursors to the free steroid. This includes DHEA sulfate, estrone sulfate, pregnenolone sulfate, and cholesterol sulfate, all to their unconjugated forms (DHEA, estrone, pregnenolone, and cholesterol, respectively). The encoded protein is found in the endoplasmic reticulum, where it is present as a homodimer. Clinical significance A congenital deficiency in the enzyme is associated with X-linked ichthyosis, a scaly-skin disease affecting roughly 1 in every 2,000 to 6,000 males. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arylsulfatase B
Arylsulfatase B (N-acetylgalactosamine-4-sulfatase, chondroitinsulfatase, chondroitinase, acetylgalactosamine 4-sulfatase, N-acetylgalactosamine 4-sulfate sulfohydrolase, ) is an enzyme associated with mucopolysaccharidosis VI (Maroteaux–Lamy syndrome). Arylsulfatase B is among a group of arylsulfatase enzymes present in the lysosomes of the liver, pancreas, and kidneys of animals. The purpose of the enzyme is to hydrolyze sulfates in the body. ARSB does this by breaking down glycosaminoglycans (GAGs), which are large sugar molecules in the body. ARSB targets two GAGs in particular: dermatan sulfate and chondroitin sulfate.U.S. National Library of Medicine"ARSB" Genetics Home Resource, 7 November 2010, Retrieved 22 November 2010 Over 130 mutations to ARSB have been found, each leading to a deficiency in the body. In most cases, the mutation occurs on a single nucleotide in the sequence. An arylsulfatase B deficiency can lead to an accumulation of GAGs in lysosomes, which i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfatase Hydrolysis
Sulfatases 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. Sulfatases play important roles in the cycling of sulfur in the environment, in the degradation of sulfated glycosaminoglycans and glycolipids in the lysosome, and in remodelling sulfated glycosaminoglycans in the extracellular space. Together with sulfotransferases, sulfatases form the major catalytic machinery for the synthesis and breakage of sulfate esters. Occurrence and importance Sulfatases are found in lower and higher organisms. In higher organisms they are found in intracellular and extracellular spaces. Steroid sulfatase is distributed in a wide range of tissues throughout the body, enabling sulfated steroids synthesized in the adrenals and gonads t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arylsulfatase A
Arylsulfatase A (or cerebroside-sulfatase) is an enzyme that breaks down sulfatides, namely cerebroside 3-sulfate into cerebroside and sulfate. In humans, arylsulfatase A is encoded by the ''ARSA'' gene. Pathology A deficiency is associated with metachromatic leukodystrophy, an autosomal An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosomal (sex chromosome) pairs, which may have different structures. The DNA in autosom ... recessive disease. Biochemistry Enzyme regulation Arylsulfatase A is inhibited by phosphate, which forms a covalent bond with the active site 3-oxoalanine. ; References Further reading * * * * * * * * * * * * * * * * * * External links GeneReviews/NCBI/NIH/UW entry on Arylsulfatase A Deficiency - Metachromatic Leukodystrophy OMIM entries on ARSA Deficiency * * * {{hydrolase-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arylsulfatase
Arylsulfatase (EC 3.1.6.1, sulfatase, nitrocatechol sulfatase, phenolsulfatase, phenylsulfatase, ''p''-nitrophenyl sulfatase, arylsulfohydrolase, 4-methylumbelliferyl sulfatase, estrogen sulfatase) is a type of sulfatase enzyme with systematic name ''aryl-sulfate sulfohydrolase''. This enzyme catalyses the following chemical reaction : an aryl sulfate + H2O \rightleftharpoons a phenol + sulfate Types include: *Arylsulfatase A (also known as "cerebroside-sulfatase") *Arylsulfatase B (also known as "''N''-acetylgalactosamine-4-sulfatase") *Steroid sulfatase (formerly known as "arylsulfatase C") * ARSC2 * ARSD *ARSE *ARSF * ARSG * ARSH * ARSI * ARSJ * ARSK See also * Aryl In organic chemistry, an aryl is any functional group or substituent derived from an aromatic ring, usually an aromatic hydrocarbon, such as phenyl and naphthyl. "Aryl" is used for the sake of abbreviation or generalization, and "Ar" is used ... References Hydrolases EC 3.1.6 {{biochem-s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iduronate 2-sulfatase
Iduronate 2-sulfatase (EC 3.1.6.13; systematic name L-iduronate-2-sulfate 2-sulfohydrolase) is a sulfatase enzyme associated with Hunter syndrome. It catalyses hydrolysis of the 2-sulfate groups of the L-iduronate 2-sulfate units of dermatan sulfate, heparan sulfate and heparin. Function Iduronate 2-sulfatase is required for the lysosomal degradation of heparan sulfate and dermatan sulfate. Mutations in this X-chromosome gene that result in enzymatic deficiency lead to the sex-linked mucopolysaccharidosis type II, also known as Hunter syndrome. At least 174 disease-causing mutations in this gene have been discovered. Iduronate-2-sulfatase has a strong sequence homology with human arylsulfatase Arylsulfatase (EC 3.1.6.1, sulfatase, nitrocatechol sulfatase, phenolsulfatase, phenylsulfatase, ''p''-nitrophenyl sulfatase, arylsulfohydrolase, 4-methylumbelliferyl sulfatase, estrogen sulfatase) is a type of sulfatase enzyme with systematic name ...s A, B, and C, and human glucosa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-acetylgalactosamine-6-sulfatase
The enzyme ''N''-acetylgalactosamine-6-sulfatase (EC 3.1.6.4) catalyzes the chemical reaction of cleaving off the 6-sulfate groups of the ''N''-acetyl-D-galactosamine 6-sulfate units of the macromolecule chondroitin sulfate and, similarly, of the D-galactose 6-sulfate units of the macromolecule keratan sulfate. This enzyme belongs to the family of hydrolases, specifically those acting on sulfuric ester bonds. The systematic name of this enzyme class is ''N''-acetyl-D-galactosamine-6-sulfate 6-sulfohydrolase. Other names in common use include chondroitin sulfatase, chondroitinase, galactose-6-sulfate sulfatase, acetylgalactosamine 6-sulfatase, ''N''-acetylgalactosamine-6-sulfate sulfatase, and ''N''-acetylgalactosamine 6-sulfatase. This enzyme participates in glycosaminoglycan degradation and degradation of glycan structures. Deficiency Morquio syndrome is a rare birth defect caused by a deficiency in this essential enzyme. Treatment options include enzyme replacement therapy E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebroside-sulfatase
Cerebroside-sulfatase (EC 3.1.6.8, arylsulfatase A, cerebroside sulfate sulfatase) is an enzyme with systematic name cerebroside-3-sulfate 3-sulfohydrolase. This enzyme catalyses the following chemical reaction : a cerebroside 3-sulfate + H2O \rightleftharpoons a cerebroside + sulfate This enzyme hydrolyses galactose-3-sulfate residues in a number of lipids. See also * Arylsulfatase A Arylsulfatase A (or cerebroside-sulfatase) is an enzyme that breaks down sulfatides, namely cerebroside 3-sulfate into cerebroside and sulfate. In humans, arylsulfatase A is encoded by the ''ARSA'' gene. Pathology A deficiency is associated with m ... References External links * {{Portal bar, Biology, border=no EC 3.1.6 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lysosomal Storage Disorders
Lysosomal storage diseases (LSDs; ) are a group of over 70 rare inherited metabolic disorders that result from defects in lysosomal function. Lysosomes are sacs of enzymes within cells that digest large molecules and pass the fragments on to other parts of the cell for recycling. This process requires several critical enzymes. If one of these enzymes is defective due to a mutation, the large molecules accumulate within the cell, eventually killing it. Lysosomal storage disorders are caused by lysosomal dysfunction usually as a consequence of deficiency of a single enzyme required for the metabolism of lipids, glycoproteins (sugar-containing proteins), or so-called mucopolysaccharides. Individually, lysosomal storage diseases occur with incidences of less than 1:100,000; however, as a group, the incidence is about 1:5,000 – 1:10,000. Most of these disorders are autosomal recessively inherited such as Niemann–Pick disease, type C, but a few are X-linked recessively inherited, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroid Sulfate
Steroid sulfates are endogenous sulfate esters of steroids. They are formed by steroid sulfotransferases via sulfation of endogenous steroids like cholesterol and steroid hormones. Although steroid sulfates do not bind to steroid hormone receptors and hence are hormonally inert, they can be desulfated by steroid sulfatase and in this way serve as precursors and circulating reservoirs for their active unsulfated counterparts. In addition, some steroid sulfates have biological activity in their own right, for instance acting as neurosteroids and modulating ligand-gated ion channels such as the GABAA and NMDA receptors among other biological targets. List of endogenous steroid sulfates Endogenous steroid sulfates include: * Cholesterol sulfate (formed from cholesterol by SULT2B1b) * Pregnenolone sulfate (formed from pregnenolone by SULT2A1 and SULT2B1a) * sulfate (formed from by SULT2A1 and SULT1E1) * Androstenediol sulfate (formed from androstenediol) * Androsterone sul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lysosome
A lysosome () is a membrane-bound organelle found in many animal cells. They are spherical vesicles that contain hydrolytic enzymes that can break down many kinds of biomolecules. A lysosome has a specific composition, of both its membrane proteins, and its lumenal proteins. The lumen's pH (~4.5–5.0) is optimal for the enzymes involved in hydrolysis, analogous to the activity of the stomach. Besides degradation of polymers, the lysosome is involved in various cell processes, including secretion, plasma membrane repair, apoptosis, cell signaling, and energy metabolism. Lysosomes act as the waste disposal system of the cell by digesting used materials in the cytoplasm, from both inside and outside the cell. Material from outside the cell is taken up through endocytosis, while material from the inside of the cell is digested through autophagy. The sizes of the organelles vary greatly—the larger ones can be more than 10 times the size of the smaller ones. They were dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
