ABSTRACT
The chemical synthesis of the zwitterionic disaccharide 2 is described that corresponds to the repeating unit of the O-specific polysaccharide (1) of the gram-negative human pathogen Shigella sonnei. Passive hemolysis inhibition tests using a hyperimmune rabbit serum raised against S. sonnei showed that the serologic activity of the disaccharide 2 is nearly 2- to 3-fold higher than those of its component monosaccharides. NMR data of 2 are in support of the proposed structure of the O-specific polysaccharide.
Subject(s)
Disaccharides/chemical synthesis , Disaccharides/immunology , O Antigens/chemistry , O Antigens/immunology , Shigella sonnei/immunology , Shigella sonnei/metabolism , Animals , Complement System Proteins/immunology , Erythrocytes/immunology , Galactose/analogs & derivatives , Galactose/chemistry , Guinea Pigs , Hemolysis , Lipopolysaccharides/immunology , Monosaccharides/chemistry , Monosaccharides/immunology , Nuclear Magnetic Resonance, Biomolecular , O Antigens/metabolism , Rabbits , Sheep , Stereoisomerism , Uronic Acids/chemistryABSTRACT
An improved quantitative micromethod is described for the assay of antigenically active bacterial lipopolysaccharides and their immunodeterminant oligosaccharides. The method which is capable of measuring antigens in nanogram quantities yields the same sensitivity as the microcomplement fixation without the limitations of this method. The use of the method was demonstrated on Shigella sonnei phase 1 and phase ii lipopolysaccharide antigens and immunodeterminants.
