Publications

• A new analytical bench assay for the determination of arylsulfatase a activity toward galactosyl-3-sulfate ceramide: implication for metachromatic leukodystrophy diagnosis.

  Morena F., di Girolamo I., Emiliani C., Gritti A., Biffi A., Martino S.

  Here, we present the design and validation of a new assay for the diagnosis of metachromatic leukodystrophy. The method is highly specific, simple, reproducible, and straightforward. In our spectrophotometric method, the determination of arylsulfatase A (ARSA) activity toward the natural substrate ... >> More

  Here, we present the design and validation of a new assay for the diagnosis of metachromatic leukodystrophy. The method is highly specific, simple, reproducible, and straightforward. In our spectrophotometric method, the determination of arylsulfatase A (ARSA) activity toward the natural substrate, galactosyl-3-sulfate ceramide (or sulfatide), is performed using neat sulfatide without chemical modification. This confers to the assay high analytical specificity. The hydrolyzed sulfatide is monitored upon inclusion of the colorimetric reagent Azure A. The nonhydrolyzed sulfatide-Azure A is recovered and measured at a wavelength of λ = 650 nm. Thus, ARSA activity toward the sulfatide is obtained by subtracting the nonhydrolyzed sulfatide from the total sulfatide used in the enzyme reaction (sulfatide-Azure A present in a parallel assay performed in the absence of ARSA). Within a clinical context, our method definitely discriminated between healthy subject samples and metachromatic leukodystrophy patient samples, and, therefore, it is suitable for diagnostic applications and for monitoring the efficacy of therapeutic treatments in patients or animal models. << Less

  Anal. Chem. 86:473-481(2014) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Crystal structure of a covalent intermediate of endogenous human arylsulfatase A.

  Chruszcz M., Laidler P., Monkiewicz M., Ortlund E., Lebioda L., Lewinski K.

  The structures of human arylsulfatase A crystals soaked in solutions containing 4-methylumbelliferyl phosphate and O-phospho-DL-tyrosine have been determined at 2.7- and 3.2-A resolution, respectively. The formylglycine in position 69, a residue crucial for catalytic activity, was unambiguously id ... >> More

  The structures of human arylsulfatase A crystals soaked in solutions containing 4-methylumbelliferyl phosphate and O-phospho-DL-tyrosine have been determined at 2.7- and 3.2-A resolution, respectively. The formylglycine in position 69, a residue crucial for catalytic activity, was unambiguously identified in both structures as forming a covalent bond to the phosphate moiety. A hydroxyl group is present at the Cbeta of residue 69 and the formation of one out of two possible stereomeric forms is strongly favoured. The structures confirm the importance of the gem-diol intermediate in the arylsulfatase's catalytic mechanism. The presence of an apparently stable covalent bond is consistent with the weak phosphatase activity observed for human arylsulfatase A. The structures of the complexes suggest that phosphate ions and phosphate esters inhibit arylsulfatase in non-covalent and covalent modes, respectively. The metal ion present in the active site of arylsulfatase A isolated from human placenta is Ca(2+) and not Mg(2+) as was found in the structure of the recombinant enzyme. << Less

  J. Inorg. Biochem. 96:386-392(2003) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Sulphogalactolipid sulphohydrolase activity of arylsulphatase purified from a marine gastropod Charonia lampas.

  Hatanaka H., Egami F., Ishizuka I., Nagai Y.

  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 sam ... >> More

  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. << Less

  Biochim Biophys Acta 438:176-185(1976) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.