The structural characterization of the O-polysaccharide antigen of the lipopolysaccharide of Escherichia coli serotype O118 and its relation to the O-antigens of Escherichia coli O151 and Salmonella enterica O47

Mild acid hydrolysis of the lipopolysaccharide produced by Escherichia coli 0118 H16 standard strain (NRCC 6613) afforded an O-polysaccharide (O-PS) composed of a-galactose 2-acetamidoylamino-2 6-dideoxy-L-galactose 2-acetamido-2-deoxy-D-glucose ribitol and phosphate (1 1 1 1 1) From DOC-PAGE sugar and methylation analyses one- and two-dimensional NMR spectroscopy capillary electrophoresis-mass spectrometry hydrolysis and sequential Smith-type periodate oxidation studies the O-PS was determined to be an unbranched linear polymer having the structure [6)-alpha-D-Galp-(1 -> 3)-alpha-L-FucpNAm-(1 -> 3)-beta-D-GlcpNAc-(1 -> 3)-Rib-ol-5-P-(0 ->](n) The structure of the O-PS is consistent with the reported DNA data on the O-antigen gene-cluster of E coli 0118 and interestingly the O-PS is similar to the structures of the O-antigens of Salmonella enterica 047 and E colt 0151 H10 reference strain 880-67 as predicted from the results of DNA sequencing of their respective O-antigen gene-clusters (C) 2010 Elsevier Ltd All rights reserved