Structure of the O2O antigen of Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia

The O-antigen polymer recovered from the reference strain for Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia serogroup O2O, by mild acid hydrolysis of the lipopolysaccharide, was found to contain d-rhamnose and d-mannose. By means of chemical degradations and NMR studies, the repeating-unit of the polymer was deduced to be a linear tetrasaccharide with the structure shown. →-λ-d-Manp-(1→3)-βd-Rhap-(1→2)-λd-Rhap-(1→