L. D. Varbanets, Т. V. Bulyhina, L. А. Pasichnyk, N. V. Zhytkevich

Zabolotny Institute of Microbiology and Virology,
National Academy of Sciences of Ukraine, Kyiv;
e-mail: varbanets_imv@ukr.net

Received: 02 September 2018; Accepted: 13 December 2018

This review analyzed literature data, as well as our own research on lipopolysaccharides (LPS) of gram-negative bacteria, focusing mainly on Pantoea agglomerans, a member of the Enterobacteriaceae fami­ly. The unique structures of O-specific polysaccharide chains of LPS from Pantoea agglomerans represented by both linear and branched tetra- and pentasaccharide repeating units were described for the first time. The heterogeneity of the LPS molecule itself and the presence of several LPS in the bacterial cell, which differ in the structure of lipids A, O-specific polysaccharide chains, serological activity, as well as endotoxic properties, such as toxicity and pyrogenicity, were shown. Such heterogeneity represents one of the mechanisms of LPS multifunctionality. Based on the antigenicity of LPS, serotyping of P. agglomerans strains and their assignment to 10 serogroups were carried out for the first time. The high immunomodulatory activity of P. agglomerans LPS suggests the possibility to use their oligosaccharide fragments in the development of conjugated vaccines against diseases caused by gram-negative bacteria.