Structural analysis of a novel polysaccharide of the lipopolysaccharide-deficient extremophile Gram-negative bacterium Thermus thermophilus HB8.

A novel polysaccharide was isolated from the extremophile
Gram-negative bacterium Thermus thermophilus HB8. Its
structural characterization employed compositional and methylation
analyses, and 2D 1H and 13C NMR spectroscopy.
Various chemical degradations (methanolysis and Smith degradation)
were also carried out in order to depolymerise this
complex macromolecule, and subsequent chemical and spectroscopic analyses were also carried out on the obtained fragments.
All the data suggested a novel polymeric structure
that consists of a disaccharide repeating unit to which a branching
trisaccharide chain is linked, although not stoichiometrically.