Structure of the O-polysaccharide of Aeromonas hydrophila O:34; a case of random O-acetylation of 6-deoxy-l-talose

The O-polysaccharide of Aeromonas hydrophila O:34 was obtained by mild-acid degradation of the lipopolysaccharide and studied by chemical methods and NMR spectroscopy before and after O-deacetylation. The polysaccharide was found to contain d-Man, d-GalNAc and 6-deoxy-l-talose (l-6dTal), and the following structure of the tetrasaccharide repeating unit was established:<fig loc="display"><link locator="fx1"></fig>where 6dTalI is O-acetylated stoichiometrically at position-2 and 6dTalII carries no, one or two O-acetyl groups at any positions. [Copyright &y& Elsevier]