Structural characterization of polysaccharides expressed by Burkholderia oklahomensis E0147

• Burkholderia oklahomensis E0147 expressed two distinct lipopolysaccharides (LPS).
• We analyzed its LPS using GC/MS and NMR.
• O-antigen contains disaccharide repeats: [3)-β-d-Glcp-(1→3)-2OAc-α-l-6dTalp-(1→]n.
• The presence of a co-extracted exopolysaccharide (EPS).
• EPS: [3)-2OAc-β-d-Galp-(1→4)-α-d-Galp-(1→3)-β-d-Galp-(1→5)-β-d-Kdop-(2→]n.

Burkholderia oklahomensis E0147 is a US isolated bacterium believed to express a similar O-antigen to type A structure of the highly pathogenic species, Burkholderia pseudomallei. Both species are genetically closely related. Lipopolysaccharide was collected from E0147 and structurally characterized to test this hypothesis. Glycosyl composition and linkage analyses in conjunction with 1D and 2D 1H and 13C NMR spectroscopy showed that the O-antigen was a repeating disaccharide with the following structure:[3)-β-d-Glcp-(1→3)-2OAc-α-l-6dTalp-(1→]nNMR spectroscopy also revealed the presence of a co-extracted exopolysaccharide previously described in B. pseudomallei, with the structure:[3)-2OAc-β-d-Galp-(1→4)-α-d-Galp-(1→3)-β-d-Galp-(1→5)-β-d-Kdop-(2→]n.

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