Skoklyuk L. Immunochemical and biological properties of Rahnella aquatilis lipopolysaccharides.

The immunochemical and biological properties of Rahnella aquatilis lipopolysaccharides (LPS) have been investigated. Their chemical idenfication showed that LPS tested contain all components which are characteristic for this type of polymers: KDO, heptose, glucose, galactose, fuсose and mannose. Lipids A of LPS studied were characterized by single diagnostic оxyacid - 3 oxytetradecanoic. R. aquatilis LPS were presented by two low molecular weight fractions of core-oligosaccharides and one high molecular weight fraction of O-specific polysaccharide. The structures of O-specific polysaccharide of R. aquatilis 95U003 and 95U004 were identical to one of the structures of O-PS of type strain R. aquatilis 33071. On the basis of cross-reactivity R. aquatilis strains investigated were divided into three serogroups. In order to decrease toxicity and pyrogeneity chemical modification of LPS studied was performed. As a result of modification of R. aquatilis LPS retained their serological activity and only R. aquatilis 96U037 LPS modified tin complexes with hydrazones of benzo (para-dimetilamіinobenz) aldehydes, completely lost the activity of the antigen. LPS displayed positive effect on the activity of cells-effectors of the immune system of macroorganism. It was first shown a direct cytotoxic effect of LPS on the development of cancer cells (sarcoma 37). These data make the investigated LPS promising drugs for a correction of the immune status of the immune system.