Aryl sulfatases

Metachromatic leukodystrophy AR Aryl sulfatase A Accumulation of sulfatide in brain see text 1,2, Ch. 40... 

In chymotrypsin and other serine proteases the imidazole moiety of histidine acts as a general base not as a nucleophile as is probably the case in the catalysis of activated phenyl ester hydrolysis by (26). With this idea in mind, Kiefer et al. 40) studied the hydrolysis of 4-nitrocatechol sulfate in the presence of (26) since aryl sulfatase, the corresponding enzyme, has imidazole at the active center. Dramatic results were obtained. The substrate, nitrocatechol sulfate, is very stable in water at room temperature. Even the presence of 2M imidazole does not produce detectable hydrolysis. In contrast (26) cleaves the substrate at 20°C. Michaelis-Menten kinetics were obtained the second-order rate constant for catalysis by (26) is 10 times... 

Eosinophils are attracted by proteins released by T cells, mast cells and basophils [eosinophil chemotactic factor of anaphylaxis (ECF-A)]. They bind schistosomulae coated with IgG or IgE, degranulate and release major basic protein, which is toxic. Eosinophils also release histaminase and aryl sulfatase, which inactivates histamine and Slow reacting substance of anaphylaxis (SRS-A). This results in antiinflammatory effects and inhibits migration of granulocytes to the site of injury. 

IR spectroscopy Removal of sulfate by hydrolysis in mild acid Removal of sulfate by solvolysis in dioxane Removal of sulfate by aryl-sulfatase A... 

Mucilage has protective functions for the root meristem and improves root-soil contact by inclusion and aggregation of soil particles. It may also contribute to P desorption and to the exclusion of toxic elements (Al, Cd, Pb) by complexation with galacturonates, mainly in exchange with Ca2+ (Neumann and Romheld, 2002). Secreted enzymes contribute to the extracellular enzyme pool it has been shown that the activity of extracellular enzymes, such as phophatases, proteases, and aryl-sulfatases, exhibit more activity in the rhizosphere relative to the bulk soil and may have a dramatic effect on the cycling of nutrients such as P, N, and S (Badalucco and Nannipieri, 2007). 

Figure 1. Extraction scheme used for /3-glucuronidase/aryl sulfatase-hydrolyzed 9-THC urines indicating derivation of the H, E-I, and E-II fractions...

Moeller et al. Water/ acetone p-Glucuronidase-aryl-sulfatase SPE (Chromabond C-18 column) GC/MS (pentafluoropropyl deriv) 15... 

Herska M, Moscovich DG, Kalian M, Gottlieb D, Bach G (1987 Mar) Aryl sulfatase a deficiency in psychiatric and neurologic patients. Am J Med Genet 26(3) 629-635 lype M et al (2006) Ann Ind Acad Neurol 9 110-112... 

Succinic dehydrogenase Cytochrome oxidase Acid phosphatase Aryl sulfatase Catalase... 

The yield of acid phosphatase was 11%, as compared with 30% for aryl sulfatase and 15% for ribonuclease. Obviously, in the attempt to obtain pure preparations of intracellular components, it is inevitable that losses be encountered. Such procedures are therefore not suited for obtaining an estimate of the quantitative distribution of intracellular components. Approximately 5-9% of the lysosomal enzymes—aryl sulfatase, acid phosphatase, and ribonuclease—were present in the free form. The remaining 91-95% of the activities of these enzymes were in the latent form and required alteration of the permeability or disruption of the lysosomal membrane to become active. 

Six hours after intravenous administration of 0.08 mg/kg [ C]-benzo[a]pyrene to rabbits. 30% and 12% of the dose was excreted in the bile and urine, respectively (Chipman et al. 1982). Excretion of activity into the bile was biphasic over a period of 30 hours with apparent half-lives of 0.27 and 4.623 hours for the rapid and slow phases, respectively. Treatment of the bile and urine with p -glucuronidase and aryl sulfatase increased the amount of activity in the bile and urine that was extractable into ethyl acetate indicating the presence of glucuronide and sulfate conjugates. 

Incubate urine, bile, liver at 36°C, 3 h 5 j,L P-glucuronadase/ aryl sulfatase (helix pomatia, Merck) Homogenate tissues (4 1 in CH8N2O3) Vortex/Centrifuge Use supernatant... 

Another group of enzymes modified by vanadate are the sulfhydrases (such as serine sulfhydrase) and sulfatases (e.g. aryl sulfatases). Serine sulfhydrase catalyses the conversion of cysteine to serine with liberation of H2S [Equation (5.7)]. Vanadate at a... 

Proposed mechanism for the catalytic hydrolysis of the sulfate ester bond by the active form of aryl sulfatase-B (AS-B), and the structure (right) of the active centre of the vanadate AS-B complex, otherwise containing the substrate sulfate. The active centre also accommodates a seven-coordinated calcium ion, ligated to three aspartates (one of which is in the Y-mode), an asparagine and two 0X0 anions of the sulfate/vanadate. Structure modified from that provided in ref. 95. 

Fedecka-Bniner, B., Anderson, M., and Epel, D. (1971). Control of enzyme synthesis in early sea urchin development Aryl sulfatase activity in normal and hybrid embryos. Dev. Biol. 25 655-671. 

Bile acid glucuronides may be hydrolyzed by -glucuronidase (EC 3.2.1.31) from bovine liver or the digestive juice of Helix pomatia (S41). The latter enzyme preparation also contains sulfatase activity (S41), but this is likely to be an aryl sulfatase which may not use bile acid sulfates as substrates. 

A. suum and H. diminuta contain O- and Af-deacetylase activity, aryl sulfatase, and both acid and alkaline phosphatases (16,21). The cestode H. diminuta can hydrolyze both a-... 

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