The structure of the carbohydrate backbone of the lipooligosaccharide from an alkaliphilic Halomonas sp.

The structure of the carbohydrate backbone of the core-lipid A region of the lipooligosaccharide (LOS) of the alkaliphilic and slightly halophilic bacterium Halomonas sp. has been elucidated. The LOS was fully deacylated, dephosphorylated, and reduced at the free reducing end. The structure, obtained by means of compositional analysis, 2D NMR spectroscopy, and MALDI mass spectrometry, was determined as the following: beta-GlcA down arrow 2 beta-Glc-(1 -> 2)-alpha-Hep-(1 -> 4)-alpha-Hep-(1 -> 5)-alpha-Kdo-(2 -> 6)-beta-GlcN-(1 -> 6)-GlcNol 3 up arrow alpha-Glc-(1 -> 6)-beta-Glc All sugars are D-pyranoses; Hep is L-glycero-b-manno-heptose and Kdo is 3-deoxy-D-manno-oct-2-ulosonic acid. (C) 2010 Elsevier Ltd. All rights reserved.