Sulphatases

Arylsulphatases.—Incubation of normal human fibroblasts with chloroquine at physiological pH released arylsulphatase A activity into the medium. The 

Nishimura, and M. Irie, Chem. and Pharm. Bull. Japan), 1974, 22, 2739. 

The purification of an arylsulphatase A from sheep brain has been accomplished by affinity chromatography on immobilized concanavalin A and pH-dependent polymerization and depolymerization of the enzyme, which is a glycoprotein containing o-glucose and D-mannose (25% total) and sialic acid (0.5%),  

An enzyme electrode for the assay of sulphate ion is based on inhibition of the hydrolysis of 4-nitrocatechol sulphate by arylsulphatase, which is used in an immobilized form on a platinum electrode,  

The sulphatase A (mol. wt. 1.07 x 10 ) from bovine liver is a glycoprotein containing D-galactose (8), o-mannose (14), 2-amino-2-deoxy-D-glucose (18), and terminal, non-reducing 5-acetamido-3,5-dideoxy-D- /jceru-D- a/acro-2-nonulosonic acid (8 moles mole ), and traces of L-fucose and D-glucose. The implications of studies of this enzyme to metachromatic leukodystrophy were discussed. 

A purification procedure has been described for an atypical arylsulphatase A which exists in chicken brain. Investigation of the properties of the enzyme revealed inter alia that the molecule is a glycoprotein. 

Four protein peaks showing arylsulphatase activity have been isolated from the gut of the giant African snail Achatina achatina via ion-exchange chromatography and gel filtration. The existence of multiple forms of the enzyme (pH optima 6.0, 5.8, 6.5, 6.3 mol. wts. 11.0 x 10 , 5.0 x 10 , 9.3 x 10 , and 11.0 X 10 respectively) was discussed in relation to their possible involvements in the various metabolic cycles of the organism. 

Cerebroside Sulphatases.—Cerebroside sulphatase (arylsulphatase A) from human liver did not form a stable complex when chromatographed with a 12-fold excess of its physiological activator protein. The activator was shown to complex with substrates (sulphatides) of the enzyme and with products (cerebrosides) of the enzyme action. 

Acidic forms of human cerebroside sulphatase have been partially purified from invertebrates Tethya aurantium (Porifera), Patella vulgata (mollusca), Maja squinado (Arthropoda), Martlasterias glacialis (Echinodermata), and Microcosmus sulcatus (Tunicata). Enzyme preparations thus obtained cleaved cerebroside sulphates only in the presence of either specific detergents, e.g. taurodeoxycholate, or an activator protein isolated from human liver. On a molar basis, less of the activator protein was required to achieve the same activation as detergent. 

L-Iduronic acid 2-suIphate Sulphatase.—Commercially available sodium heparinate has been sequentially treated with methanolic 0.06 molar hydrogen chloride and nitrous acid. The non-degraded material was separated by gel filtration from the nonsulphated and monosulphated disaccharides produced. The latter ones, obtained in 10% yield, have been used as a substrate for the 

Kitahata, S. Okada, and A. Misaki, Agric. Biol Chem., 1979, 43, 151. 408 Takahashi and H. Nishibe,/. Biochem. (Tokyo), 1978, 84, 1467. 

2-Acetamido-2-deoxy-D-galactose 6-sulphate sulphatase activity has been identified in rat skin (see p. 533).  

A sulphatase, which liberates sulphate from UDP-2-acetamido-2-deoxy-D-galactose 6-sulphate (the nucleotide occurring in quail egg white at high concentration), has been isolated from quail oviduct.The tissue also contained sulphatase activities for UDP-2-acetamido-2-deoxy-D-galactose 4-sulphate and nitrocatechol sulphate but these activities were removed from the 6-sulphatase fraction during purification. The UDP-2-acetamido-2-deoxy-D-galactose 6- 

Nakanishi, M. Tsuji, H. Habuchi, and S. Suzuki, Biochem. Biophys. Res. Commun., 1979, 89, 863. 

respectively). Although predominantly an exo-sulphatase, the enzyme catalysed the hydrolysis of sulphate from internal 2-acetamido-2-deoxy-D-glucose 6-sulphate residues at a low rate. The enzyme which was inhibited by aluminium, Hg, and phosphate, sulphate, and cyanide ions, displayed highest activity in kidney and cultured fibroblasts, but was present in all human tissues tested. 

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Hydrolases. Enzymes catalysing the hydrolytic cleavage ofC —O, C —N and C —C bonds. The systematic name always includes hydrolase but the recommended name is often formed by the addition of ase to the substrate. Examples are esterases, glucosidases, peptidases, proteinases, phospholipases. Other bonds may be cleaved besides those cited, e.g. during the action of sulphatases and phosphatases. 

Inhibition of steroid sulphatase and sulphotransferase Steroid sulphotransferase catalyses the addition of sulphate to steroidal compounds whilst steroid sulphatase catalyses the reverse reaction. In vitro studies have demonstrated that a metabolite of genistein, 4-ethylphenol, can inhibit sulphotransferase (Harris et al, 2000). Sulphoconjugates of daidzein have also been found to potently inhibit these enzymes in vitro (Wong and... 

Careful examination of the yellowish sediment obtained after spinning down the crude mitochondrial fraction showed it was frequently overlaid with loosely packed, fluffy material —the fluffy layer. Experiments from de Duve s and, later, Novikoff s laboratories in the 1950s demonstrated that the lighter, lysosomal fraction was enriched in a number of hydrolases including acid phosphatase, aryl sulphatase, B glucuronidase, RNAase, and a peptidase, cathepsin. All the enzymes had optimal pHs in the acid range (pH 5-pH 6). Density... 

II Hunter X-linked iduronate sulphatase Dermatan sulfate Heparan sulfate... 

III Sanfilippo III a Autosomal recessive Heparan sulphatase Heparan sulfate... 

S. D. Gorham, M. Cantz, Arylsulphatase B, an exo-Sulphatase for Chondroitin 4-Sul-phate Tetrasaccharide , Hoppe-Seyler s Z. Physiol. Chem. 1978, 359, 1811-1814. 

Glass IA, Lam RC, Chang T, Roitman E, Shapiro LJ, Shackleton CH (1998) Steroid sulphatase deficiency is the major cause of extremely low oestriol production at mid-pregnancy a urinary steroid assay for the discrimination of steroid sulphatase deficiency from other causes. Prenat Diagn 18 789-800... 

Sulphatides Metachromatic leukodystrophy (MLD) Arylsulphatase A (galactose-3-sulphatase) 22ql3.31-qter... 

Dermatan sulfate (DS) and Heparan MPS II, Hunter Iduronate-2-sulphatase Xq27.3-28... 

Dissolve 5000 Fishman units of mixed glucuroni-dase/sulphatase (from Helix pomatid) in 1 ml of acetate buffer (pH 5). Adjust 10 ml of the urine to pH 5 with 0. IM hydrochloric acid, add 1 ml of the enzyme solution, and incubate at 37° for about 12 hours. 

Adjust 20 ml of urine to pH 5 with 0.1 M hydrochloric acid, add 2 ml of acetate bi er (pH 5), and 10 000 Fishman units of mixed gluciwoiiidase/ sulphatase (from. Helixpomatid), and heat in a water-bath at 60° for 2 hours. Pom tiie urine on to Ml imbuffered Tox Elut column (see Reagent. / ipendix) and leave for 2 to 3 minutes to allow the sMnple to soak into the column. Place a 50-ml test-tube under the coliunn outlet and pour on to the coliunn 20 ml of a mixture of chloroform isopropyl alcohol (9 1). When the elution is complete, insert into tile top of the column a hollow rubber stopper... 

Adjust the urine sample to pH 5 by the addition of dilute hydrochloric acid. For each 9 volumes of urine add 1 volume of acetate buffer pH 5) containing 5000 Fishman units/ml of mixed glucuronidase/ sulphatase (from Helixpomatia), and incubate the mixture at 31 for 24 hours. Centrifuge, pour the supernatant liquid on to a column of Amberlite XAD-2 resin, wash the column with 50 ml of water, and then elute the steroids with 100 ml of ethanol. Evaporate the ethanol using a rotary film evaporator, dissolve the residue in 0.5 ml of ethanol, and add 2 ml of cyclohexane. 

In those cases where a suitable antibody for radioimmunoassay is not available, a full multi-component screening procedure is necessary, and also needs to be undertaken as a confirmatory test in cases where the nature of the anabolic steroid is not known. The full analysis involves the separation of the glucuronic acid and sulphate conjugate fractions and their separate hydrolysis followed by GC-MS of their silyl or methoxime-silyl derivatives. It should be noted that the sulphatase in Helix pomatia will not hydrolyse the sulphate conjugates of the 1713-hydroxy steroids, which require mild acid hydrolysis. 

Mucopolysaccharidosis II (Hunter Syndrome) Iduronate 2-sulphatase HS, DS Short stature, skeletal dysplasia, coarse facial features, joint stiffness, visceromegaly, cardiac disease, comeal clouding, CNS involvement... 

Mucopolysaccharidosis IIIA (Sanfilippo A syndrome) Heparan N -sulphatase HS Coarse hair, CNS involvement, aggressive behaviour, dysmorphic features (-1-/—), skeletal dysplasia (-1-/—)... 

Maroteaux-Lamy syndrome) 4-sulphatase joint stiffness, visceromegaly, cardiac disease, comeal clouding... 

Endoplasmic reticulum sulphatase modifying factors sulphatases Golgi... 

Hunter s syndrome (type II) Initially, this disease was erroneously classified as type I-H. Its nosological independence and X-chromosomal recessive transmission were recognized in 1964 (A. Nja). The disease is based on a deficiency of L-iduron-sulphate sulphatase and sulphoiduronate sulphatase. The syndrome may appear in a moderate or severe form. 

Morquio s syndrome (type IV) This syndrome is a result of a galactosamine-6-sulphatase deficiency (type A) or a beta-galactos-idase deficiency (type B) (L. Morquio, 1929 X. F. Brailsford, 1929). 

P6. Pasqualini, J. R., Cedard, L., Nguyen, B. L., and Alsatt, E., Differences in the activity of human term placenta sulphatases for steroid ester sulphates. Biochim. Biophys. Acta 189, 177-179 fl967). 

Fischer, G., and Jatzkewitz, H., The activator of cerebroside sulphatase Purification from human liver and identification as a protein. Hoppe-Seyler s Z. Physiol. Chem. 356, 605-613 (1975). 

Murphy, J. V., Wolfe, H. J., Balazs, E. A., and Moser, H., A patient with deficiency of arylsulfatase A,B,C, and steroid sulphatase associated with storage of sul tide, cholesterol and glycosaminoglycans. In Lipid Storage Diseases (J. Bernsohn and H. Gorsman, eds.), pp. 67-110. Academic Press, New York, 1971. 

The supply of oestrogen produced endogenously for the continued maintenance of tumour growth may be supplemented by the cancerous tissue itself (see review by Miller [30]). Over half [31] of human breast cancer cells synthesize oestrogen from androgen precursors in vitro [32-35]. Studies [35] on the synthesis in situ of oestrogens from human breast tumours by either the aromatase enzyme (from androstenedione) or a sulphatase enzyme (from oestrone sulphate) have shown that the latter pathway predominates. The sulphatase laromatase activity ratio is about 10 at normal in vivo concen-... 

Organic phosphorus and the remainder of the organic sulphur are associated with soil organic matter in the form of esters (i.e. C-O-P, C-O-S), and these nutrients are mineralized by the actions of various extracellular phosphatase and sulphatase enzymes ( biochemical mineralization ). 

Speir, T.W. and Ross, D.J. (1978) Soil phosphatase and sulphatase. In Burns, R.C. (ed.) Soil Enzymes. Academic Press, London, pp. 197-250. 

Kang, H. and Freeman, C. (1999) Phosphatase and aryl-sulphatase activities in wetland soils annual variation and controlling factors. Soil Biology and Biochemistry31,449-454. 

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