title: Nigerooligosaccharide acceptor reaction of Streptococcus sobrinus glucosyltransferase GTF-I.
abstract: Nigerose and nigerooligosaccharides served as acceptors for a glucosyltransferase GTF-I from cariogenic Streptococcus sobrinus to give a series of homologous acceptor products. The soluble oligosaccharides (dp 5-9) strongly activated the acceptor reaction, resulting in the accumulation of water-insoluble (1-->3)-alpha-D-glucan. The enzyme transferred the labeled glucosyl residue from D-[U-13C]sucrose to the 3-hydroxyl group at the non-reducing end of the (1-->3)-alpha-D-oligosaccharides, as unequivocally shown by NMR 13C-13C coupling patterns. The values of the 13C-13C one-bond coupling constant (1J) are also presented for the C-1-C-6 of the 13C-labeled alpha-(1-->3)-linked glucosyl residue and of the non-reducing-end residue.
authors.affiliation: Department of Chemistry, National Defense Medical College, Tokorozwa, Saitama, Japan. hmukasa@ndmc.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Mukasa
authors.forename: A
authors.initials: A
authors.lastname: Shimamura
authors.forename: H
authors.initials: H
authors.lastname: Tsumori
mesh_terms: D001426:Bacterial Proteins; D002855:Chromatography, Thin Layer; D004187:Disaccharides / Q000737:chemistry / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D005936:Glucans / Q000737:chemistry; D005964:Glucosyltransferases; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D009682:Magnetic Resonance Spectroscopy; D009844:Oligosaccharides / Q000138:chemical synthesis / Q000378:metabolism*; D010429:Pentoses / Q000737:chemistry; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D013291:Streptococcus / Q000201:enzymology*; D013395:Sucrose / Q000737:chemistry / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D004187:Disaccharides; D005936:Glucans; D009844:Oligosaccharides; D010429:Pentoses; D011506:Proteins; C014637:laminaribiose; C067118:GTF-I protein, Streptococcus; D013395:Sucrose; D005964:Glucosyltransferases; C489364:glucosyltransferase I