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)

Arylsulfatase A (arylsulfate sulfohydrolase, EC 3.1.6.1), a mammalian lysosomal enzyme, is initially synthesized as a 69, 67 and 64 kDa precursor polypeptide in a prostate carcinoma cell line PC-3SF12, in HeLa cells and in a normal human embryonic lung cell line WI-38, respectively. These precursor polypeptides are secreted into the medium or processed to mature enzymes of apparent molecular mass 66, 64 or 62 kDa in PC-3SF12, HeLa or WI-38 cells, respectively. The precursor and mature polypeptides in WI-38 cells are phosphorylated, and the phosphate is lost upon treatment with endo-beta-hexosaminidase H. Arylsulfatase A is also shown to be sulfated in WI-38 cells. The presence of castanospermine, an inhibitor of sulfation of the second N-acetylglucosamine residue of the chitobiose core, does not reduce the extent of sulfation of arylsulfatase A, suggesting that either terminal sugars or the protein is sulfated. Sulfation may have a protective function similar to that of terminal sialic acid residues in glycoproteins. Although the subcellular location of arylsulfatase A is identical in PC-3SF12 and in WI-38 cells, pulse-chase experiments indicate that arylsulfatase A protein has a slower turnover in the prostate carcinoma cell line than it does in the normal human lung cell line. The differences in the apparent molecular weights of arylsulfatase A in the normal and carcinoma cell lines are shown to be due to variations in the carbohydrate content of the enzyme. The apparent molecular mass of the polypeptide chain obtained after endo-beta-hexosaminidase H treatment is 59 kDa, a value which is identical for all three cell lines studied here. These results suggest the possibility of an enhanced activity of terminal glucosyltransferase enzymes in carcinoma cell lines and in tumor tissues. Arylsulfatase A may be a useful marker for studying transformation-related processes in human cell lines.
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PMID:Phosphorylation and sulfation of arylsulfatase A accompanies biosynthesis of the enzyme in normal and carcinoma cell lines. 286 59

The biosynthesis of lysosomal acid phosphatase was studied in a normal human embryonic lung cell line, WI-38. Cells were labeled with radioactive leucine under a variety of conditions, the enzyme was immunoprecipitated using a monospecific antiserum raised against human liver lysosomal acid phosphatase, and the products were separated by electrophoresis and were visualized by fluorography. Lysosomal acid phosphatase constitutes 60% of the total tartrate-inhibitable acid phosphatase in WI-38. It is initially synthesized as a high-molecular-weight precursor polypeptide of 69 kDa. The precursor polypeptide is rapidly glycosylated and processed to a mature enzyme of 53-45 kDa via intermediates of 65 and 60 kDa in WI-38 cells. The 69-kDa precursor polypeptide is also converted to larger precursor polypeptides of 74 and 80 kDa. The multiplicity of precursor polypeptides is due at least in part to differences in the glycosylation and phosphorylation of the polypeptides. Sensitivity of phosphorylated oligosaccharide chains from precursor, mature and small polypeptides to endo-beta-hexosaminidase H-catalyzed cleavage suggests the presence of high-mannose phosphorylated oligosaccharide chains similar to those present on many other lysosomal enzymes. The effects of tunicamycin and ammonium chloride were also studied. In contrast to the effect of ammonium chloride on arylsulfatase A secretion, the lysosomal acid phosphatase in WI-38 cells was not secreted in the presence of NH4Cl. This is consistent with the existence of an alternate route for the transfer of lysosomal acid phosphatase into lysosomes. This alternate route may be the reason that I-cell fibroblasts contain a normal level of lysosomal acid phosphatase.
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PMID:Biosynthesis and processing of lysosomal acid phosphatase in cultured human cells. 390 32

Arylsulfatase cloned from a marine aerobic Gram-negative bacterium, Pseudoalteromonas carrageenovora, was overexpressed in Escherichia coli with 10 microM IPTG induction. The expressed recombinant arylsulfatase was purified to homogeneity from the harvested cells through osmotic disruption and column chromatography methods, such as DEAE-cellulose anion exchange chromatography and Heparin-Sepharose affinity chromatography. The purified arylsulfatase was kinetically characterized using the synthetic substrate of phenolic ester, p-nitrophenyl sulfate (pNPS). One unit of arylsulfatase catalyzes the liberation of 1.0 micromol p-nitrophenol from pNPS per minute. The purified enzyme has a specific activity of 468 U/mg with a purification yield of 27% from the cell lysate, and exhibited an estimated molecular mass of 33 kDa in SDS-PAGE analysis. The precursor polypeptide of 36 kDa was processed by releasing a putative signal peptide, and the mature arylsulfatase of 33.1 kDa with a N-terminal sequence of S-E-T-K-N was trafficked to periplasmic space. The enzyme had optimum reaction conditions for activity at pH 7.0 and at a temperature range of 40-45 degrees C. The apparent K(M) and k(cat) of the enzyme for hydrolysis of pNPS at pH 7.0 and at 45 degrees C were determined to be 1.15 mM and 1000 s-1, respectively. Based on inhibitor studies along with optimal pH values and preferential periplasmic location of the enzyme, we suggest that the recombinant arylsulfatase from P. carrageenovora is probably similar to the Klebsiella sulfatase with serine residue in the active site.
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PMID:Purification and characterization of the recombinant arylsulfatase cloned from Pseudoalteromonas carrageenovora. 1559 66