Syntheses of O-antigen polysaccharide fragments of nitrogen-fixing rhizobacteria of the genus Azospirillum

Abstract

Fragments of O-antigen polysaccharides of nitrogen-fixing rhizobacteria of the genus Azospirillum isolated from natural sources may greatly vary in the monosaccharide composition, molecular weight, as well as in the presence of side chains and branching sites along the main chain. These variations, along with the differences in purity and homogeneity of the samples, hamper investigations of the role of individual components of O-antigen polysaccharides of the rhizobacteria Azospirillum in interactions with plants, including important cereal crops. Therefore, synthetic oligosaccharides, which correspond to O-antigen polysaccharide fragments of rhizobacteria of the genus Azospirillum and have a strictly defined structure and high purity, are highly demanded. The review summarizes the data on the synthesis of these oligosaccharide fragments as promising tools for investigation of the mechanism of formation of a symbiotic association with plants.