Structural Differences in Fructans Elaborated by Streptococcus mutana and Strep. salivarius

抄録

D-Fructans synthesized from sucrose by cell-free systems of strains of Streptococcus mutans and Strep. salivarius have been shown by methylation and enzymatic studies to have different glycosidic linkages. The cold water-insoluble D-fructans from Strep.mutans strain BHT and JC-1 have inulin-type structures consisting β-(2→l)-D-fructo-furanosidic linkages, with average repeating units of 8 and 27 sugar residues, respectively, whereas the water-soluble fructan from Strep. salivarius strain HHT has a levan-type branched structure consisting β-(2→6)-D-fructofuranosidic linkages with an average repeating unit of 9 sugar residues. The solubility properties of these fructants are discussed on the basis of the structural differences.