title: Isolation and characterization of non-labeled and 13C-labeled mannans from Pichia pastoris yeast.
abstract: Mannans from genetically modified Pichia pastoris yeast, used for overproduction of neural cell adhesion molecule protein, grown on normal media or on uniformly 13C-labeled glucose and methanol, were isolated and characterized by high-field (750 MHz) NMR spectroscopy. Fully 13C-labeled oligosaccharide fragments were prepared from mannans by acetolysis. According to the data obtained, the mannan is made up of a main chain of alpha-(1-->6)-linked mannopyranosyl residues, substituted at 0-2 with alpha-mannopyranosyl or a alpha-D-Manp-(1-->2)-beta-D-Manp-(1-->2)-beta-D-Manp-( 1-->2)-alpha-D-Manp- group, and with much lower content of substitution with beta-D-Manp-(1-->2)-alpha-D-Manp-. A fraction of these oligosaccharide side chains is again substituted with alpha-D-Glcp or alpha-D-GlcpNAc through a phosphodiester linkage to the 6 position of the first mannopyranosyl residue. Improved conditions of acetolysis, cleaving all alpha-(1-->6) linkages, but not beta-mannoside linkages, are proposed.
authors.affiliation: Department of Chemistry, Carlsberg Laboratory, Copenhagen, Denmark.
authors.forename: E
authors.initials: E
authors.lastname: Vinogradov
authors.forename: B O
authors.initials: BO
authors.lastname: Petersen
authors.forename: J O
authors.initials: JO
authors.lastname: Duus
mesh_terms: D002240:Carbohydrate Sequence; D002247:Carbon Isotopes; D002848:Chromatography, DEAE-Cellulose; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008351:Mannans / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D010843:Pichia / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D018076:DNA, Complementary; D008351:Mannans; D011134:Polysaccharides