The linkage between O-specific caryan and core region in the lipopolysaccharide of Burkholderia caryophylli is furnished by a primer monosaccharide.

From the lipopolysaccharide (LPS) fraction of the plant-pathogenic bacterium Burkholderia caryophylli, the linkage between O-specific caryan and core region was characterised. The LPS fraction was first treated with 48% aqueous HF at 4 degrees C and successively with 1% acetic acid at 100 degrees C. A main oligosaccharide representing the carbohydrate backbone of the core region and a portion of the caryan (three unit of caryose) was isolated by high-performance anion-exchange chromatography. Compositional and methylation analyses, matrix-assisted laser desorption/ionisation mass spectrometry and 2D NMR spectroscopy identified the structure: [carbohydrate structure: see text]. The above residues are alpha-linked pyranose rings, if not stated otherwise. Hep is L-glycero-D-manno-heptose, Car is 4,8-cyclo-3,9-dideoxy-L-erythro-D-ido-nonose and Kdo is 3-deoxy-D-manno-oct-2-ulosonic acid. This finding indicates that QuiNAc residue is the primer monosaccharide, which connects the core oligosaccharide to caryan O-chain.