Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.1 (sulfatase)
3,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Four acid hydrolase activities are demonstrable by light microscopy in pigment epithelial cell lysosomes of rats (Royal College of Surgeons--RCS) with inherited retinal dystrophy and in control (Fischer) rats. The enzymes include acid phosphatase, aryl sulfatase, N-acetyl-beta-glucosaminidase, and esterase activities. No marked differences are observed in distribution or staining intensity of lysosomes in the two strains of rat. Acid hydrolase activities are not localized in sites other than lysosomes. Acid phosphatase and aryl sulfatase activities are also demonstrable by electron microscopy. In both strains, acid phosphatase reaction product is localized to various forms of lysosomes in pigment epithelial cells. A diffuse precipitate, considered to be nonspecific in origin, is seen in the cytoplasm, apical processes, outer segments (control), and outer segment debris (RCS). The precipitate is probably due to adsorption of lead from the incubation medium or of lead phosphate that diffuses from heavy accumulations in nearby lysosomes. Aryl sulfatase reaction product, in contrast to acid phosphatase, is localized to far fewer lysosomes and there is virtually no nonspecific precipitate. The findings indicate that lysosomes of RCS pigment epithelial cells possess several cytochemically demonstrable acid hydrolase activities. There is no evidence for the localization of acid phosphatase (or aryl sulfatase) activities in sites other than lysosomes.
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PMID:Localization of lysosomal enzymes in retinal pigment epithelium of rats with inherited retinal dystrophy. 62 65

Human N-acetylgalactosamine-6-sulfate sulfatase (6-sulfatase) activity is measured by using as a substrate a sulfated tetrasaccharide obtained by digesting purified chondroitin-6-sulfate (C-6-S) with testicular hyaluronidase. The amount of inorganic sulfate released is measured turbidimetrically. The enzyme from human kidney has a pH optimum of 4.8; its activity is augmented by low levels of NaCl and inhibited by phosphate and high levels of NaCl. Free glucuronate, acetylgalactosamine, inorganic sulfate, polymeric C-6-S, or tetrasaccharide obtained from chondroitin-4-sulfate do not affect the enzyme activity. The method may be used for the diagnosis of Morquio disease since extracts of Morquio fibroblasts are devoid of 6-sulfatase activity.
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PMID:N-acetylgalactosamine-6-sulfate sulfatase in man. Absence of the enzyme in Morquio disease. 82 Jul 16

Sulphatide, cerebroside 3-sulphate was hydrolyzed at a considerable rate by arylsulphatase (aryl-sulphate sulphohydrolase, EC 3.1.6.1) purified from a marine gastropod, Charonia lampas. However, it was scarcely hydrolyzed by glycosulphatase (sugar-sulphate sulphohydrolase, EC 3.1.6.3) from the same origin. The same was observed with seminolipid, a sulphoglycerogalactolipid. The enzymatic characteristics of both sulphogalactolipid and sulphohydrolase activities of the arylsulphatase were determined as follows. The enzyme activities are stimulated by the addition of sodium taurodeoxycholate and MnCl2. The pH optimum of sulphatide sulphohydrolase activity was pH 5.0, while seminolipid sulphohydrolase activity had maximum activity at pH 5.5. Both of these pH versus activity curves were broad. The Km value was 6.22-10-5 M for both substrates. However, the V values were sulphatide were lower by a factor of one-third than those with seminolipid. These enzyme activities were inhibited by substrates of the arysulphatase, i.e., p-nitrophenyl sulphate, p-nitrocatechol sulphate, ascorbate 2-sulphate and each other sulphogalactolipid, but not by glucose 6-sulphate. Sulphate and phosphate anions inhibited both of the enzyme activities.
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PMID:Sulphogalactolipid sulphohydrolase activity of arylsulphatase purified from a marine gastropod Charonia lampas. 93 79

Extracts of isolated rat peritoneal mast cells were demonstrated to contain appreciable quantities of arysulfatase activity. The enzyme was inhibited by both phosphate and sulfate ions and demonstrated a pH optimum of 5.0. The enzyme was recovered in the eluate of DE-52 columns and appeared to have a m.w. of 150,000 of Sephadex G-200 gel filtration. These findings and the anomalous kinetic behavior of the enzyme suggest that at least part of the enzymatic activity is of the arylsulfatase IIA type. While spontaneous release of the enzyme was observed, challenge of isolated rat mast cells with a goat anti-rat IgE serum resulted in a significant increase in release of the enzyme. The arylsulfatase activity extracted from isolated rat mast cells demonstrated comparable activity in inactivating slow reacting substance of anaphylaxis (SRS-A) to that described for human eosinophil and lung arylsulfatase.
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PMID:Functional characterization of rat mast cell arylsulfatase activity. 99 97

The effects of various compounds on ascorbate-2-sulfate sulfohydrolase and arylsulfatase (EC 3.1.6.1) activities in the copurified preparation from the liver of Charonia lampas were investigated. The former activity was competively inhibited by inorganic phosphate and sulfate. The latter was not affected by sulfate. Higher concentrations of sodium chloride inhibited the former and activated the latter. Neither of the activities was inhibited by sulfhydryl reagents. Both activities were competively inhibited by the other substrate.
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PMID:Effects of various compounds on the ascorbate-2-sulfate sulfohydrolase and arylsulfatase activities copurified from the liver of Charonia lampas. 115 Jun 40

Twenty hair samples obtained from Bolivian mine workers who chewed 3-8 g of coca leaves daily for several years were analyzed for cocaine and its main metabolites, benzoylecgonine (BZE) and ecgonine methyl ester (EME). A new method was developed for the detection and quantitation of cocaine and its metabolites, BZE and EME, from hair in a single procedure. The hair samples were washed, cut into 56 segments (2-cm length), pulverized, and incubated with phosphate buffer and the enzyme beta-glucuronidase-arylsulfatase. After solid phase extraction and derivatization with pentafluoropropionic anhydride/pentafluoropropanol, the drugs were identified and measured by gas chromatography/mass spectrometry (GC/MS) using deuterated cocaine, BZE, and EME as internal standards. The method is reproducible (cocaine, CV = 8%; BZE, CV = 14%) and the detection limit for cocaine and BZE was 0.1 ng/mg, for EME 1 ng/mg. In the different hair segments, cocaine was found to be present in concentrations between 1.4 to 50.6 ng/mg, benzoylecgonine from 0.4 to 17.6 ng/mg, and ecgonine methyl ester traces below the calibration curve of approximately 12.9 ng/mg. In 95% of the cases cocaine exceeded BZE and EME in concentration.
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PMID:Identification and quantitation of cocaine and its metabolites, benzoylecgonine and ecgonine methyl ester, in hair of Bolivian coca chewers by gas chromatography/mass spectrometry. 129 35

The human colon adenocarcinoma cell lines SW 948, SW 1116, and SW 1222 were tested for their ability to sort and internalize lysosomal enzymes. The biosynthesis of the lysosomal enzymes cathepsin B, arylsulfatase A, and beta-hexosaminidase in these cell lines exhibits no significant differences to that in human fibroblasts. The intracellular targeting of newly synthesized hydrolases to the lysosomes relies in colon carcinoma cells on the mannose 6-phosphate receptor system. Both the cation-independent mannose 6-phosphate receptor (CI-MPR) and the cation-dependent mannose 6-phosphate receptor are expressed in all colon carcinoma cell lines investigated. Endocytosis of lysosomal enzymes via mannose 6-phosphate receptors is reduced in colon carcinoma cells as compared with human fibroblasts. SW 1116 cells were shown to be deficient in receptor-mediated endocytosis of mannose 6-phosphate containing ligands. Ligands of other endocytic receptors as well as the fluid-phase marker horseradish peroxidase were internalized at normal rates. While antibodies against CI-MPR bind to the surface of SW 1116 cells, these antibodies cannot be internalized. These data suggest that the cycling of CI-MPR is specifically impaired in SW 1116 cells.
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PMID:Biosynthesis and endocytosis of lysosomal enzymes in human colon carcinoma SW 1116 cells: impaired internalization of plasma membrane-associated cation-independent mannose 6-phosphate receptor. 132 52

The correct intracellular sorting of lysosomal enzymes such as arylsulfatase A depends on the presence of mannose 6-phosphate residues on high mannose type oligosaccharides. The arylsulfatase A cDNA contains three potential N-glycosylation sites, two of which are utilized. We have mutated one or two of the N-glycosylation sites and analyzed the glycosylation, phosphorylation, and intracellular sorting of the mutant arylsulfatase A polypeptides. The results show that each of the three glycosylation sites (I, II, and III) can be glycosylated, but glycosylation at sites I and II is mutually exclusive. In mutants with one oligosaccharide side chain at positions I, II, or III all side chains can acquire mannose 6-phosphate residues irrespective of their location. This demonstrates spatial flexibility of the phosphotransferase, which specifically recognizes lysosomal enzymes and initiates the addition of mannose 6-phosphate residues on oligosaccharide side chains. However, these mutants have different intracellular sorting efficiencies and seem to use different (mannose 6-phosphate receptor-dependent and -independent) sorting pathways.
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PMID:In vitro mutagenesis of potential N-glycosylation sites of arylsulfatase A. Effects on glycosylation, phosphorylation, and intracellular sorting. 135 93

The mannose 6-phosphate (Man6P) residues that are necessary for the targeting of newly synthesized lysosomal proteins are dephosphorylated after delivery of lysosomal proteins to lysosomes. To examine the role of lysosomal acid phosphatase (LAP) for the dephosphorylation of Man6P residues in lysosomal proteins, the phosphorylation of endogenous lysosomal proteins and of internalized arylsulfatase A was analyzed in mouse L-cells that overexpress human LAP. Non-transfected L-cells dephosphorylate endogenous lysosomal proteins slowly (half time approximately 13 h) as well as internalized arylsulfatase A. A more than 100-fold overexpression of LAP in these cells did not affect the dephosphorylation rate. Control experiments showed that the internalized arylsulfatase A and overexpressed LAP partially colocalize and that under in vitro conditions purified LAP does not dephosphorylate arylsulfatase A. Taken together, these results indicate that LAP is not the mannose 6-phosphatase that dephosphorylates lysosomal proteins after their delivery to lysosomes.
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PMID:Lysosomal acid phosphatase is not involved in the dephosphorylation of mannose 6-phosphate containing lysosomal proteins. 135 23

We used perfused rat livers to investigate the role of endosomes versus lysosomes in the hydrolysis of endocytosed material. When perfusions were performed at 37 degrees C with 125I-asialoorosomucoid, 125I-galactosylated albumin, or 125I-mannosylated albumin, there was a 15-min lag before trichloroacetic acid-soluble degradation products were detected. Furthermore, no hydrolysis was detected at 16 degrees C, indicating that there was no significant prelysosomal degradation of these proteins. Since detection by this method depends on extensive hydrolysis, we subsequently used three small synthetic molecules from which fluorescent products are generated by a single cleavage. These were 4-methylumbelliferyl sulfate, 4-methylumbelliferyl phosphate, and 4-methylumbelliferyl-beta-D-glucosaminide, which are substrates for aryl sulfatase, acid phosphatase, and beta-hexosaminidase, respectively. Using the first two compounds, hydrolysis was detected after 3 min at 37 degrees C and still occurred, albeit to a reduced extent, at 16 and 4 degrees C. This indicates that aryl sulfatase and acid phosphatase are active prelysosomally. We found a different result with 4-methylumbelliferyl-beta-D-glucosaminide. At 37 degrees C, there was a greater than 15-min lag before hydrolysis products were measured; furthermore, hydrolysis ceased at 16 degrees C, indicating that beta-hexosaminidase is active lysosomally. Taken together, these findings show that there is selective activation and/or delivery of hydrolases along the endocytic pathway.
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PMID:Hydrolases in intracellular compartments of rat liver cells. Evidence for selective activation and/or delivery. 167 61


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