title: Structure of a new hexasaccharide from the coaggregation polysaccharide of Streptococcus sanguis 34.
abstract: The major constituent of a coaggregation polysaccharide from Streptococcus sanguis 34 is a hexasaccharide, isolated as the alditol. The proposed structure is alpha-D-GalpNAc-(1----3)-beta-L-Rhap-(1----4)-beta-D-Glcp-(1----6) -beta-D-Galf- (1----6)-beta-D-GalpNAc-(1----3)-D-Galol, based upon g.l.c.-m.s. of alditol acetates and partially methylated alditol acetates, f.a.b.-m.s., 1H-n.m.r. spectroscopy, g.l.c.-m.s. of trimethylsilylated (+)- and (-)-2-butyl glycosides, and cleavage by alpha-N-acetylgalactosaminidase. The structural deduction was facilitated by cleavage of the hexasaccharide at the furanoside linkage by 48% hydrogen fluoride, and reduction of the product, to yield alpha-D-GalpNAc-(1----3)-beta-L-Rhap-(1----4)-beta-D-Glcp-(1----6) -D-Galol.
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009844:Oligosaccharides / Q000302:isolation & purification*; D011135:Polysaccharides, Bacterial; D013298:Streptococcus sanguis / Q000276:immunology*
chemical_list: D009844:Oligosaccharides; D011135:Polysaccharides, Bacterial