Structure of the lipopolysaccharide O-antigen of endophytic Pseudomonas sp. strain L1

The O-specific polysaccharide (OPS) was isolated from the lipopolysaccharide of Pseudomonas sp. Strain L1, the endophytic bacteria of Lolium perenne (ryegrass) plants growing in soil in an industrial area in the Silesia region (Zabrze, Southern Poland). The high-molecular-weight O-PS fraction liberated from Pseudomonas sp. L1 lipo-polysaccharide by mild acid hydrolysis was studied using chemical methods, MALDI-TOF mass spectrometry, and 1D and 2D NMR spectroscopy techniques. It was found that the O-specific polysaccharide was built of tetra-saccharide repeating units composed of D-FucpN, D-Fucp4N, and two D-QuipN residues. The following structure of the O-PS of Pseudomonas sp. Strain L1 was established:-> 4)-a-d-FucpN-(1 -> 3)-a-d-QuipN-(1 -> 3)-beta-d-QuipN-(1 -> 3)-a-d-Fucp4N-(1 ->