The O-polysaccharide of Escherichia coli O112ac has the same structure as that of Shigella dysenteriae type 2 but is devoid of O-acetylation: a revision of the S. dysenteriae type 2 O-polysaccharide structure

Carbohydr Res. 2008 Apr 7;343(5):977-81. doi: 10.1016/j.carres.2008.02.002. Epub 2008 Feb 10.

Abstract

The O-antigen structure of Shigella dysenteriae type 2 was reinvestigated using chemical modifications along with high-resolution 2D (1)H and (13)C NMR spectroscopy. The O-antigen was found to contain a pyruvic acid acetal, which was overlooked in an early study, and the following revised structure of the pentasaccharide repeating unit was established: where approximately 70% GlcNAc residues bear an O-acetyl group at position 3. The O-antigen of Escherichia coli O112ac was found to have the same carbohydrate structure but to lack O-acetylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbohydrate Sequence
  • Chromatography, Gas
  • Escherichia coli / chemistry*
  • Hydrolysis
  • Lipopolysaccharides / chemistry
  • Lipopolysaccharides / isolation & purification
  • Magnetic Resonance Spectroscopy
  • Molecular Sequence Data
  • Monosaccharides / analysis
  • O Antigens / chemistry*
  • O Antigens / isolation & purification
  • Pyruvates / analysis
  • Shigella dysenteriae / chemistry*
  • Trifluoroacetic Acid / analysis
  • Trifluoroacetic Acid / chemistry

Substances

  • Lipopolysaccharides
  • Monosaccharides
  • O Antigens
  • Pyruvates
  • pyruvic acid acetal
  • Trifluoroacetic Acid