Structural studies of the O-polysaccharide of Pragia fontium 97U124 containing 2-acetamido-2,4,6-trideoxy-4-(d-glyceroyl)amino-d-glucose

The O-polysaccharide was obtained by acid hydrolysis of the lipopolysaccharide of Pragia fontium 97U124 and studied by sugar analysis and 1D and 2D NMR spectroscopy. A new bacillosamine derivative, 2-acetamido-2,4,6-trideoxy-4-(d-glyceroyl)amino-d-glucose (d-QuiNAc4NAcyl), was identified as a polysaccharide constituent. The following structure of the O-polysaccharide was established:→3)-α-l-FucpNAc-(1→3)-α-l-FucpNAc-(1→3)-β-d-QuipNAc4NAcyl-(1→This structure is closely related to that of the d-QuiNAc4NAc-containing O-polysaccharide of Pseudomonas aurantiaca IMV 31 established earlier (Knirel, Y. A.; Zdorovenko, G. M.; Veremeychenko, S. N.; Lipkind, G. M.; Shashkov, A. S.; Zakharova, I. Y.; Kochetkov, N. K. Bioorg. Khim.1988, 14, 352–358).

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Pragia fontium is a recently proposed species of Enterobacteriaceae. ► The O-polysacharide was isolated from P. fontium 97U124 and analyzed. ► The full structure of the O-unit of the polysaccharide was established. ► An N-(d-glyceroyl) derivative of bacillosamine was identified in the O-unit.