Structure of the O-chain polysaccharide of three strains of Pseudomonas syringae ssp. savastanoi

Abstract

The structure of the O-chain portion of the lipopolysaccharide isolated from three different strains of Pseudomonas syringae ssp. savastanoi has been determined by chemical and NMR spectral analysis. For all of the strains the O-chain consists of a tetrasaccharide repeating unit of three α-L-Rhap and one terminal nonreducing α-D-Fucp3NAc. Two rhamnosyl residues are 3-linked and the third one is 2,3-linked. LPS from an olive strain, avirulent on oleander, was shown to attenuate the response of oleander plants inoculated with a homologous strain.