title: Structural and immunological studies of the Escherichia coli K7 (K56) capsular polysaccharide.
abstract: The structure of the Escherichia coli K7 capsular polysaccharide has been investigated by a combination of chemical and spectroscopic methods. The Structure of the repeating unit of the polymer was found to be goes to 3)-beta-D-ManNAcA-(1 leads to 4)-beta-D-Glc-(1 goes to ; the O-6 atom of the D-glucosyl residue in the repeating unit is acetylated. The K7 polysaccharide is cross-reactive with the Streptococcus pneumoniae type 3 polysaccharide, the structure of which had previously been determined; our n.m.r. studies of the S. pneumoniae type 3 polysaccharide are in accord with this structure. The E. coli K7 and K56 capsular antigens have been shown by serology and 13C-n.m.r. spectroscopy to be identical.
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D003429:Cross Reactions; D004926:Escherichia coli / Q000276:immunology*; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D013045:Species Specificity; D013296:Streptococcus pneumoniae / Q000276:immunology
chemical_list: D011135:Polysaccharides, Bacterial