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

Abstract

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 1H, 13C, and 31P 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: [formula: see text] and for the tetraglycosyl phosphate repeating unit of the extracellular polysaccharide: [-(PO3-)-->3)-beta-D-GlcpNAc-(1-->2)-6-d-alpha-L-gul-Hepp -(1-->2)-3-d-beta-D-threo-Penp-(1-->3)-6-d-alpha-L-gul-He pp-]n