Lipo-oligosaccharide of the Campylobacter lari type strain ATCC 35221. Structure of the liberated oligosaccharide and an associated extracellular polysaccharide

Lipo-oligosaccharide (LOS) from phenol-water extraction of cells of the Campylobacter lari type strain (ATCC 35221) was separated as a water-insoluble gel of low relative molecular mass (M(r)) from a water-soluble extracellular polysaccharide of high M(r). Structural investigations were performed on the liberated oligosaccharide and the extracellular polysaccharide, variously using H-1, C-13, and P-31 NMR spectroscopy, linkage analysis, and fast atom bombardment-mass spectrometry of permethylated derivatives of the glycans and their products of chemical and enzymic degradation. The following structures are proposed for the highly branched region of the LOS: [GRAPHICS] AEP= 2-aminoethylphosphate and for the tetraglycosyl phosphate repeating unit of the extracellular polysaccharide: [-(PO3-)-->3)-beta-D-Glc p NAc-(1-->2)-6-d-alpha-L-gulHep p-(1-->2)-3-d-beta-D-threo-Pen p-(1-->3)-6-d-alpha-L-gul-Hep p-](n).