Structure of the lipopolysaccharide O-antigen of Pseudomonas cepacia serotype A.
The O-antigenic polysaccharides of the lipopolysaccharides produced by three isolates of Pseudomonas cepacia serogroup A were analysed by composition, methylation, periodate oxidation, and two-dimensional nuclear magnetic resonance methods. They were found to be identical linear unbranched polymers of a repeating trisaccharide unit containing 2-acetamido-2-deoxy-D-galactose and L-rhamnose residues (2:1) and have the structure [-->3)-alpha-D-GalpNAc-(1-->3)-beta-D-GalpNAc-(1-->4)-alpha-L-Rhap -(1-->]n.