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

• Published in: Carbohydrate research Vol. 345; no. 18; pp. 2664 - 2669
• Main Authors: MacLean, Leann L., Liu, Yanhong, Vinogradov, Evgeny, Perry, Malcolm B.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 10.12.2010
• Subjects: Escherichia coli; NMR; O-Antigen; Polysaccharide; Structure; O-Antigen; NMR; Structure; Polysaccharide; Escherichia coli
• DOI: 10.1016/j.carres.2010.10.004
• ISSN: 0008-6215

Mild acid hydrolysis of the lipopolysaccharide produced by Escherichia coli O118:H16 standard strain (NRCC 6613) afforded an O-polysaccharide (O-PS) composed of d-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)-α- d-Gal p-(1→3)-α- l-Fuc pNAm-(1→3)-β- d-Glc pNAc-(1→3)-Rib-ol-5- P-(O→] n The structure of the O-PS is consistent with the reported DNA data on the O-antigen gene-cluster of E. coli O118 and interestingly, the O-PS is similar to the structures of the O-antigens of Salmonella enterica O47 and E. coli O151:H10 reference strain 880-67, as predicted from the results of DNA sequencing of their respective O-antigen gene-clusters.