Characterization of a lipopolysaccharide O antigen containing two different trisaccharide repeating units from Burkholderia cepacia serotype E (O2)

The O antigen of the lipopolysaccharide of Burkholderia cepacia serotype E (O2) was shown by a combination of methylation analysis, partial hydrolysis, NMR, and mass spectrometric methods to be a high molecular weight polysaccharide composed of two different trisaccharide repeating units in the ratio 2:1. The major trisaccharide component is composed of two α-d-mannopyranosyl and one β-d-galactopyranosyl residues with the structure, [→ 2)-α-d-Manp-(1 → 2)-α-d-Manp-(1 → 4)-β-d-Galp-(1 → ]n The minor trisaccharide component is a d-mannan composed of two α- and one β-d-mannopyranosyl residues with the structure. [→ 2)-α-d-Manp-(1 → 2)-α-d-Manp-(1 → 3)-β-d-Manp-(1 → ]n