title: Characteristics of asparagine-linked sugar chains of sphingolipid activator protein 1 purified from normal human liver and GM1 gangliosidosis (type 1) liver.
abstract: Asparagine-linked sugar chains of sphingolipid activator protein 1 (SAP-1) purified from normal human liver and GM1 gangliosidosis (type 1) liver were comparatively investigated. Oligosaccharides released from the two SAP-1 samples by hydrazinolysis were fractionated by paper electrophoresis and by Aleuria aurantia lectin-Sepharose and Bio-Gel P-4 (under 400 mesh) column chromatography. Structures of oligosaccharides in each fraction were estimated from data on their effective molecular sizes, behavior on immobilized lectin columns with different carbohydrate-binding specificities, results of sequential digestion by exoglycosidases with different aglycon specificities, and methylation analysis. Sugar chains of SAP-1 purified from normal human liver and from GM1 gangliosidosis (type 1) liver were different from each other, although both of them were derived from complex-type sugar chains. The sugar chains of the former were the following eight degradation products from complex-type sugar chains by exoglycosidases in lysosomes: Man alpha 1----6(Man alpha 1----3)Man beta 1----4GlcNAc beta 1----4GlcNAcOT, Man alpha 1----6(Man alpha 1----3)Man beta 1----4GlcNAc beta 1----4(Fuc alpha 1----6)GlcNAcOT, Man alpha 1----6Man beta 1----4GlcNAc beta 1----4GlcNAcOT, Man alpha 1----6Man beta 1----4GlcNAc beta 1----4(Fuc alpha 1----6)GlcNAcOT, Man beta 1----4GlcNAc beta 1----4GlcNAcOT, Man beta 1----4GlcNAc beta 1----4(Fuc alpha 1----6)GlcNAcOT, GlcNAc beta 1----4GlcNAcOT, and GlcNAcOT. In contrast to these, the sugar chains of the latter were sialylated and nonsialylated mono- to tetraantennary complex-type sugar chains that were not fully degraded due to a metabolic defect in acid beta-galactosidase activity.
authors.affiliation: Department of Biochemistry, Kobe University School of Medicine, Hyogo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yamashita
authors.forename: K
authors.initials: K
authors.lastname: Inui
authors.forename: K
authors.initials: K
authors.lastname: Totani
authors.forename: N
authors.initials: N
authors.lastname: Kochibe
authors.forename: M
authors.initials: M
authors.lastname: Furukawa
authors.forename: S
authors.initials: S
authors.lastname: Okada
mesh_terms: D001216:Asparagine; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002846:Chromatography, Affinity; D005677:G(M1) Ganglioside; D005733:Gangliosidoses / Q000378:metabolism*; D006023:Glycoproteins / Q000302:isolation & purification*; D006026:Glycoside Hydrolases; D006801:Humans; D008099:Liver / Q000032:analysis*; D008969:Molecular Sequence Data; D009439:Neuraminidase; D009844:Oligosaccharides / Q000302:isolation & purification*; D012016:Reference Values; D049231:Saposins; D049128:Sphingolipid Activator Proteins
chemical_list: D006023:Glycoproteins; D009844:Oligosaccharides; C483345:PSAP protein, human; D049231:Saposins; D049128:Sphingolipid Activator Proteins; D005677:G(M1) Ganglioside; D001216:Asparagine; D006026:Glycoside Hydrolases; D009439:Neuraminidase