The serological properties of the O-antigen polysaccharide region of the lipopolysaccharides are used to differentiate E. coli strains into serogroups. In this study, we report the structure elucidation of the O-specific chain of E. coli O179 using NMR data, the program CASPER and analysis of biosynthetic information available in the E. coli O-antigen Database (ECODAB). The presence of genes that encode enzymes involved in the biosynthesis of the GDP-Man and UDP-GlcA within the O-antigen gene cluster of the bacteria indicates that the corresponding residues could be present in the polysaccharide. Furthermore, the occurrence of four genes that encode for glycosyltransferases indicates that the polysaccharide is composed of pentasaccharide repeating units
a bioinformatics approach based on predictive glycosyltransferase functions present in ECODAB revealed that the β-d-Manp-(1→4)-β-d-Manp-(1→3)-d-GlcpNAc structural element could be present in the O-specific chain. NMR spectroscopy data obtained from homonuclear and heteronuclear 2D NMR spectra (