title: Steroid sulfatase. Biosynthesis and processing in normal and mutant fibroblasts.
abstract: Antibodies raised against steroid sulfatase purified from human placenta were used to follow the biosynthesis of this enzyme in human skin fibroblasts. Steroid sulfatase is synthesized as a membrane-bound Mr-63 500 polypeptide with asparagine-linked oligosaccharide chains. Within 2 days, newly synthesized steroid sulfatase is processed to a mature Mr-61 000 form. The decrease in size is due to processing of the oligosaccharide chains, which are cleavable by endoglucosaminidase H in both the early and the mature form of steroid sulfatase. The processing involves mannosidase(s) sensitive to 1-deoxy-manno-nojirimycin. The half-life of the steroid sulfatase polypeptides is 4 days. Synthesis of steroid-sulfatase-related polypeptides and steroid sulfatase activity were not detectable in fibroblasts from four patients with X-linked ichthyosis.
mesh_terms: D017485:1-Deoxynojirimycin; D002478:Cells, Cultured; D004721:Endoplasmic Reticulum / Q000201:enzymology; D005347:Fibroblasts / Q000201:enzymology; D005944:Glucosamine / Q000031:analogs & derivatives / Q000494:pharmacology; D006056:Golgi Apparatus / Q000201:enzymology; D006801:Humans; D007057:Ichthyosis / Q000201:enzymology; D008247:Lysosomes / Q000201:enzymology; D008358:Mannose / Q000378:metabolism; D008970:Molecular Weight; D009154:Mutation; D009844:Oligosaccharides / Q000378:metabolism; D043266:Steryl-Sulfatase; D013429:Sulfatases / Q000096:biosynthesis* / Q000172:deficiency / Q000276:immunology
chemical_list: D009844:Oligosaccharides; D017485:1-Deoxynojirimycin; D013429:Sulfatases; D043266:Steryl-Sulfatase; D005944:Glucosamine; D008358:Mannose