title: Reduction of the adherence of Streptococcus sobrinus insoluble alpha-D-glucan by endo-(1----3)-alpha-D-glucanase.
abstract: Insoluble alpha-D-glucan, previously formed on a glass surface from sucrose by the action of cell-free D-glucosyltransferases of Streptococcus sobrinus OMZ176, was significantly removed by a purified preparation of endo-(1----3)-alpha-D-glucanase (mutanase) from a strain of Pseudomonas sp. Almost complete dissociation of adherent glucan occurred at the highest enzyme concentration (40 mU/mL) tested. Synthesis and de novo adherence on glass of the glucan was markedly inhibited by the presence of mutanase, even at low concentrations (4 mU/mL or less). When compared to native glucan, the mutanase-modified glucan samples (a) contained lower proportion of D-(1----3) linkages; (b) showed lower susceptibility to mutanase and higher susceptibility to (1----6)-alpha-D-glucanase (dextranase); (c) contained larger amounts of low-molecular-weight fractions; (d) had lower intrinsic viscosities; (e) showed higher S. sobrinus cell-agglutinating activities; and (f) consisted of looser entwinement of coalescent single-stranded fibrils (a major component) and shorter double-stranded fibrils (a minor one).
authors.affiliation: Department of Preventive Dentistry, Kagoshima University Dental School, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Inoue
authors.forename: T
authors.initials: T
authors.lastname: Yakushiji
authors.forename: M
authors.initials: M
authors.lastname: Katsuki
authors.forename: N
authors.initials: N
authors.lastname: Kudo
authors.forename: T
authors.initials: T
authors.lastname: Koga
mesh_terms: D000268:Adhesiveness; D000372:Agglutination Tests; D005936:Glucans / Q000378:metabolism*; D005964:Glucosyltransferases / Q000302:isolation & purification; D006026:Glycoside Hydrolases / Q000378:metabolism*; D006868:Hydrolysis; D008745:Methylation; D008854:Microscopy, Electron; D008970:Molecular Weight; D011135:Polysaccharides, Bacterial; D012995:Solubility; D013291:Streptococcus; D014783:Viscosity
chemical_list: D005936:Glucans; D011135:Polysaccharides, Bacterial; D005964:Glucosyltransferases; D006026:Glycoside Hydrolases; C028760:endo-1,3-alpha-glucanase