title: Determination, by carbon-13 nuclear magnetic resonance spectroscopy, of the composition of glucans synthesized by enzymes of the cariogenic organism Streptococcus mutans.
abstract: The 13C-n.m.r. spectra of water-soluble and -insoluble glucans synthesized by enzymes isolated from six strains of Streptococcus mutans are interpreted. The glucans are shown to be composed primarily of alpha-(1 linked to 3)- and alpha-(1 linked to 6)-linked glucosyl residues, and the relative abundance of each linkage is estimated from peak areas. Treatment of water-insoluble glucans with dextranase is found to result in water-soluble and -insoluble products, the former enriched in alpha-(1 linked to 6)-linkages and the latter in alpha-(1 linked to 3)-linkages. The structural conclusions arrived at by 13C-n.m.r. spectroscopy are consistent with data from methylation analysis and 1H-n.m.r. spectroscopy.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D003731:Dental Caries / Q000382:microbiology; D003910:Dextranase; D005936:Glucans / Q000032:analysis* / Q000096:biosynthesis; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D012995:Solubility; D013295:Streptococcus mutans / Q000032:analysis* / Q000201:enzymology
chemical_list: D005936:Glucans; D003910:Dextranase