The O-polysaccharide from the lipopolysaccharide of Providencia stuartii O44 contains L-quinovose,a 6-deoxy sugar rarely occurring in bacterial polysaccharides

摘要

The O-polysaccharide (O-antigen) of Providencia stuartii O44:H4 (strain 3768/51) was obtained by mild acid degradation of the lipopolysaccharide and studied by sugar and methylation analyses along with ~1H and ~13C NMR spectroscopy,including 2D ~1H,~1H COSY,TOCSY,ROESY,and H-detected ~1H,~13C HSQC,and HMQC-TOCSY experiments.The O-polysaccharide was found to have a branched hexasaccharide repeating unit of the following structure.