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)

Human NK activity is known to be associated with a population of large granular lymphocytes (LGL) exhibiting several immunophenotypic surface markers including Leu-11a (NKP-15), Leu-7 (HNK-1), Leu-3a (T4), and Leu-2a (T8). Based upon correlation with cytolytic activity, Leu-11a is now considered the most specific antigenic marker for human NK cells. Present investigation compared the ultrastructure of cells expressing Leu-11a, Leu-7, Leu-3a, and Leu-2a, both in human peripheral blood lymphocytes (PBL) and the purified LGL fraction. Subcellular cytochemical reactions were investigated in Leu-7+ or Leu-11a+ PBL or LGL and in cells conjugated with K562 targets (indicating NK cytolytic potential). The surface markers, localized with monoclonal antibodies, were detected by immunoelectron microscopy by using direct or indirect avidin-biotin-peroxidase (ABC) or colloidal gold methods. A peroxidase-colloidal gold double-labeling system was used to identify subsets of Leu-7+ or Leu-11a+ cells. Previously described ultrastructural features of LGL including a villous surface, reniform nuclei, low nuclear/cytoplasm ratios, and abundant cytoplasm with vesicles, vacuoles, electron-dense granules, parallel tubular arrays (PTA), or paracrystalline inclusions were associated with Leu-7+, Leu-11a+, Leu-7+/Leu-11a+, Leu-7+/Leu-11a-, and Leu-7-/Leu-11a+ PBL or LGL. Results showed that the Leu-7+/Leu-11a+ cells were the most abundant NK cells in PBL. Lymphocyte subsets with Leu-3a or Leu-2a surface marker showed some ultrastructural features including PTA similar to Leu-7+ cells and Leu-11a+ cells, and their subsets. These T-cells appeared ultrastructurally more similar to the Leu-7+/Leu-11a- subset. Cytochemical studies showed that electron-dense cytoplasmic granules and PTA typical of the Leu-11a+ cells and Leu-7+ cells contained glycoprotein, acid phosphatase, and arylsulfatase. Large cytoplasmic vacuoles were heterogeneous and typically contained electron-dense material with DAB reactivity, membranous material, PTA, and/or paracrystalline inclusions. Glycoprotein, acid phosphatase, and arylsulfatase, and peroxidase reactive material were also found in these vacuoles. These features suggested that the vacuoles could be secondary lysosomes. The coexistence of intact PTA or degenerating PTA in the same vacuoles with paracrystalline inclusions suggested that the latter are possibly derived from PTA.
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PMID:Immunoultrastructural studies of human NK cells: I. Ultracytochemistry and comparison with T cell subsets. 355 61

We report a method for the isolation of enriched fractions of intact Golgi apparatus from neurons of 10- to 12-day-old rat brains. Neurons were prepared according to a modified method of Farooq and Norton [J. Neurochem. 31, 887-894 (1978)]. Golgi-enriched fractions were obtained after centrifugation of postmitochondrial supernatants in a discontinuous sucrose gradient. Golgi fractions 1 and 2, recovered at the interfaces of 28-34% and 34-36% sucrose densities, respectively, were examined with morphometric and enzymatic methods. Morphometric analyses showed that 21-34% of fraction 1 and 11-29% of fraction 2 consisted of intact Golgi apparatus. Lysosomes, mitochondria, ribosomes, and rough endoplasmic reticulum contaminated fraction 1 (6-10%) and fraction 2 (14-26%). Golgi fraction 1 showed a 25- to 65-fold enrichment over neurons of UDP Gal:GlcNAc galactosyltransferase, CMP-sialic acid:lactosylceramide sialyltransferase, and PAPS:cerebroside sulfotransferase activities. Golgi fraction 2 showed a 8- to 23-fold enrichment over neurons of the activities of the above glycolipid- and glycoprotein-synthesizing enzymes. The activities of the possible marker enzymes rotenone-insensitive NADH-cytochrome c reductase, succinate-cytochrome c reductase, and arylsulfatase were low or minimally elevated in the Golgi fractions. A sevenfold enrichment of Na+, K+-ATPase activities was found in the Golgi fractions. This is consistent either with significant plasma membrane contamination or with the presence of this enzyme in the neuronal Golgi apparatus.
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PMID:Isolation and characterization of an enriched Golgi fraction from neurons of developing rat brains. 400 71

Activator protein for galactosylceramide sulfatase (GSase) was purified from human liver. The activator has an approximate molecular weight of 22,000, is glycoprotein in nature, and is most probably a trimer consisting of an 8,000 dalton monomer. Monospecific rabbit antiserum raised against the activator strongly inhibited the activity of the activator. In the presence of a 10-fold or more excess of galactosylceramide sulfate (GS) on a molar basis, GS binding to the GSase activator occurred, and was saturated at an equimolar ratio. Binding studies on the GSase activator were conducted using affinity chromatography on derivatives of GS as ligands, and gel filtration of mixtures containing glycolipids and the activator. A "GS-acid" derivative, which was prepared by oxidative cleavage of sphingosine moiety in GS, and a sulfonamide derivative of GS as ligands still retained affinity for the GSase activator, while a hydrophobic ligands, an aminohexyl group did not bind completely the activator. A ligand of "galactosylceramide-acid" had weak affinity for GSase activator. These results suggest that the sulfate group and one of the two hydrocarbon chains in GS are not essential for the binding of the activator. The affinity of galactosylceramide for the GSase activator was confirmed by the detection of the lipid-protein complex on gel filtration. The activator weakly stimulated porcine GM1-beta-galactosidase activity.
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PMID:Purification and properties of galactosylceramide sulfatase activator from human liver. 408 63

Rabbit liver aryl sulfatase A (aryl-sulfate sulfohydrolase, EC 3.1.6.1) is a glycoprotein containing 4.6% carbohydrate in the form of 25 residues of mannose, seven residues of N-acetylglucosamine, and three residues of sialic acid per enzyme monomer of molecular weight 140 000. Each monomer consists of two equivalent polypeptide chains. The protein has a relatively high content of proline, glycine and leucine, and the amino acid composition of rabbit liver aryl sulfatase A is similar to that of other known liver sulfatases. Rabbit liver aryl sulfatase A catalyzes the hydrolysis of a wide variety of sulfate esters, although it appears possible that cerebroside sulfate is a physiological substrate for the enzyme because the Km is very low (0.06 mM). The turnover rate for hydrolysis of nitrocatechol sulfate or related synthetic substrates is much higher than the rate with most naturally occurring sulfate esters such as cereroside sulfate, steroid sulfates, L-tyrosine sulfate or glucose 6-sulfate. However, the turnover rate with ascorbate 2-sulfate is comparable to the rates measured using most synthetic substrates. These results are discussed in relationship to several previously described sulfatase enzymes which were claimed to have unique specificities.
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PMID:Chemical characterization and substrate specificity of rabbit liver aryl sulfatase A. 610 85

The biosynthesis of arylsulfatase A was studied in cultured fibroblasts by pulse-chase labeling with [2-3H]mannose; the enzyme was isolated by immunoprecipitation and denaturing polyacrylamide gel electrophoresis. In normal fibroblasts, and in fibroblasts from a patient with multiple sulfatase deficiency, the enzyme was synthesized as a glycoprotein of apparent molecular weight of 59,000; half of it was processed over a period of 4 days to Mr = 57,000. The precursor chain of Mr = 59,000 was secreted in the presence of 10 mM NH4Cl. An immunoprecipitable glycoprotein of normal size was synthesized by fibroblasts from two unrelated patients with metachromatic leukodystrophy, but this material disappeared within twenty hours. In fibroblasts from an individual with pseudo-deficiency of arylsulfatase A, the immunoprecipitable precursor glycoprotein was smaller (Mr = 56,000). The synthesis of cross-reactive proteins with altered properties supports the concept of allelic mutations as the genetic basis of metachromatic leukodystrophy and of arylsulfatase A pseudo-deficiency.
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PMID:Synthesis and maturation of cross-reactive glycoprotein in fibroblasts deficient in arylsulfatase A activity. 613 6

Lysosomal hydrolases produce degradation of glomerular basement membrane and may play a key role in catabolism of glycoproteins of extracellular matrix in glomeruli. Therefore we investigated activities of some lysosomal enzymes and stability of lysosomes in glomeruli of normal and nephrotic rats. Nephrosis was induced in rats by single injections of puromycin aminonucleoside. In glomeruli from nephrotic rats we found lower activities of beta-fucosidase and arylsulfatase, but activity of acid phosphatase was higher compared with control rats. Osmotic stability of lysosomes measured by release of beta-glucuronidase was decreased in nephrotic rats. Abnormal activity of lysosomal enzymes and altered physiology of lysosomes in glomeruli may be a pathogenic factor in the altered glycoprotein metabolism in nephrotic syndrome and perhaps also in other glomerular diseases.
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PMID:Glomerular lysosomal enzymes in aminonucleoside nephrosis. 617 16

Electron-dense material in clear synaptic vesicles in rat cerebral cortex and neuromuscular junctions of frog cutaneous pectoris muscle was demonstrated by using ferrocenyl cationics. Electron-dense spots were usually attached to the inner surface of the vesicular membrane. Control experiments (treatment with Triton X-100 or cetylpyridinium chloride; enzyme digestion with trypsin, hyaluronidase, neuraminidase, sulfatase and beta-glucuronidase) suggested that the electron-dense material is a glycoprotein.
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PMID:Demonstration of electron-dense material in clear synaptic vesicles using cationic ferrocenyl compounds. 633 45

A deficiency of glycoprotein neuraminidase (sialidase, acylneuraminyl hydrolase, EC 3.2.1.18) activity was found in fibroblasts from a patient with the clinical symptoms of Morquio disease type A (mucopolysaccharidosis IV A). Residual neuraminidase activity was about 5% of the mean normal activity. N-Acetylgalactosamine-6-sulfate (GalNAc-6-S) sulfatase activity was reduced to less than 1% of normal with a pH-optimum of 3.0 as expected for the severe form of Morquio disease. In peripheral leucocytes of the patient, however, neuraminidase activity but not Ga1NAc-6-S sulfatase activity was in the normal range. Mixing experiments excluded the presence of excessive amounts of inhibitors of neuraminidase activity.
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PMID:Partial deficiency of glycoprotein neuraminidase in some patients with Morquio disease type A. 642 47

Arylsulfatase C [EC 3.1.6.1] was solubilized from rat liver microsomes with Triton X-100 and purified about 2,000-fold with an overall yield of 30-40%. The purification procedure included ion-exchange chromatography, hydrophobic affinity chromatography, and gel filtration. The purified enzyme was homogeneous as judged by polyacrylamide gel electrophoresis in the presence of SDS, and its monomeric molecular weight was estimated to be about 72,000 daltons. The molecular weight of the native enzyme was about 280,000 daltons as determined by gel filtration in the presence of Triton X-100, suggesting a tetrameric structure for the enzyme molecule. The enzyme showed an isoelectric point of pH 8.1. From its strong affinity toward concanavalin A-Sepharose and colorimetric determination of neutral sugars by the phenol-sulfuric acid method, arylsulfatase C was identified as a glycoprotein. Analysis of the carbohydrates by gas-liquid chromatography demonstrated that the carbohydrate chains of arylsulfatase C were rich in mannose and N-acetyl-glucosamine, suggesting that they are the high mannose-type. This conclusion was supported by the results of digestion of the enzyme with endoglycosidase H.
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PMID:Purification and properties of arylsulfatase C from rat liver microsomes. 695 91

P-selectin glycoprotein ligand-1 (PSGL-1) is a mucin-like glycoprotein on leukocytes that is a high affinity ligand for P-selectin. Previous studies have shown that sialylation and fucosylation of PSGL-1 are required for its binding to P-selectin, but other post-translational modifications of PSGL-1 may also be important. We demonstrate that PSGL-1 synthesized in human HL-60 cells can be metabolically labeled with [35S]sulfate that is incorporated primarily into tyrosine sulfate. Treatment of PSGL-1 with a bacterial arylsulfatase releases sulfate from tyrosine, resulting in a concordant decrease in binding to P-selectin. These studies demonstrate that tyrosine sulfate on PSGL-1 functions in conjunction with sialylated and fucosylated glycans to mediate high affinity binding to P-selectin.
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PMID:Tyrosine sulfation of P-selectin glycoprotein ligand-1 is required for high affinity binding to P-selectin. 755 87


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