Isolation and characterisation of disodium (4-amino-4-deoxy-β-l-arabinopyranosyl)-(1⃗8)-(d-glycero-α-d-talo-oct-2-ulopyranosylonate)-(2⃗4)-(methyl 3-deoxy-d-manno-oct-2-ulopyranosid)onate from the lipopolysaccharide of Burkholderia cepacia

A trisaccharide was isolated from the core oligosaccharide in the lipopolysaccharide (LPS) of Burkholderia cepacia GIFU 645 (ATCC 25416, type strain) by methanolysis followed by HPLC and saponification. It was identified by MS, methylation analysis and 1H and 13C NMR spectroscopy as disodium (4-amino-4-deoxy-β-l-arabinopyranosyl)-(1⃗8)-(d-glycero-α-d-talo-oct-2-ulopyranosylonate)-(2⃗4)-(methyl 3-deoxy-d-manno-oct-2-ulopyranosid)onate. In addition to the trisaccharide derivative, methanolysis gave dimethyl (d-glycero-α-d-talo-oct-2-ulopyranosylonate)-(2⃗4)-(methyl 3-deoxy-d-manno-oct-2-ulopyranosid)onate in a relative proportion to the trisaccharide of 3:1, indicating a non-stoichiometric (∼25%) substitution of the octulosonic acid by 4-amino-4-deoxyarabinose in the LPS.