Prevotella denticola Lipopolysaccharide from a Cystic Fibrosis Isolate Possesses a Unique Chemical Structure

We report the first complete structural characterization of the lipopolysaccharide (LPS) from a cystic fibrosis (CF) clinical isolate of Prevotella denticola (B003V1S1X). Chemical, spectroscopic, and spectrometric analyses revealed a unique rough‐type LPS (LOS) structure. The structure has a highly negatively charged heptasaccharide core region containing hexoses, with the first two sugars, 3‐deoxy‐D‐manno‐oct‐2‐ulosonic acid (Kdo) and mannose, highly phosphorylated. Furthermore, the lipid A moiety has the typical structure for the genus Prevotella, and was also highly phosphorylated. Prevotella spp. is a strict anaerobe frequently detected in the airways of cystic fibrosis patients. Little is known about the role of Prevotella in the pathophysiology of cystic fibrosis. We report the first complete structural elucidation of the lipopolysaccharide from a cystic fibrosis clinical isolate of Prevotella. The unique structure is highly phosphorylated and has no heptose residues.