Purification and some properties of human liver iduronate sulfatase.
Iduronate sulfatase was purified from human liver for an investigation of the degradative pathway of dermatan sulfate. An overall 80-fold purification was achieved and, more importantly, the preparation was free of alpha-L-iduronidase, beta-glucuronidase, N-acetylgalactosamine 4-sulfate sulfatase (arylsulfatase B) and highly enriched in beta-N-acetylhexosaminidase. The liver enzyme appeared to be composed of several molecular species. The enzyme activity was optimal at pH 4.0 and its Km was 10--20 microM with sulfoiduronyl sulfoanhydromannitol. Chloride was inhibitory at high concentration and among divalent metal ions, only copper was inhibitory. Nitrocatechol sulfate was not a substrate, but did show competitive inhibition. Its Ki for iduronate sulfatase was similar to its Km for arylsulfatase, suggesting a similarity in the substrate binding sites of iduronate sulfatase and arylsulfatases.
D055598:Chemical Phenomena; D002621:Chemistry; D002845:Chromatography / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007066:Iduronate Sulfatase / Q000302:isolation & purification*; D007525:Isoelectric Focusing; D008099:Liver / Q000201:enzymology*; D012995:Solubility; D013429:Sulfatases / Q000302:isolation & purification*
D013429:Sulfatases; D007066:Iduronate Sulfatase