Structure of the hexose region of Shigella sonnei phase II lipopolysaccharide with 3-deoxy-D-manno-octulosonic acid as possible immunodeterminant and its relation to Escherichia coli R1 core.
Comparative chemical analysis (methylation, gas chromatography/mass spectrometry, periodate oxidation, etc.) of the lipopolysaccharides and degraded polysaccharides derived from Shigella sonnei phase I, phase II and galactose-deficient R mutants revealed a structure as shown: (formula: see text) 3-Deoxy-D-manno-octulosonic acid (dOclA) as an immunodeterminant was observed in the passive hemolysis inhibition test by (a) selective inhibition of the phase II system by dOclA; (b) the kinetics of the change of serological activity during mild acid treatment: 1% acetic acid abolished serological activity; (c) a lack of activity in galactose-less R mutants and reactivity with Re mutants including Salmonella minnesota Re. An enhanced sensitivity of phase II lipopolysaccharide to galactose oxidase after prolonged treatment with 1% acetic acid suggests that dOclA is linked to C-6 of the terminal or subterminal galactose. dOclA as immunodeterminant could explain some different polysaccharide structures described for Escherichia coli R1 core.
D000085:Acetates; D004926:Escherichia coli; D005692:Galactose Oxidase / Q000378:metabolism; D006461:Hemolysis; D006601:Hexoses / Q000032:analysis*; D007661:Ketoses / Q000276:immunology*; D008070:Lipopolysaccharides / Q000032:analysis* / Q000276:immunology; D008745:Methylation; D009154:Mutation; D009844:Oligosaccharides / Q000302:isolation & purification; D012764:Shigella sonnei / Q000235:genetics; D013400:Sugar Acids / Q000276:immunology*
D000085:Acetates; D006601:Hexoses; D007661:Ketoses; D008070:Lipopolysaccharides; D009844:Oligosaccharides; D013400:Sugar Acids; D005692:Galactose Oxidase