Abstract: | The data on the structure and biological activity of the lipopolysaccharide (LPS) of Yersinia as an important virulence factor are analyzed. The biological effects of LPS are characterized by dose dependence: small doses stimulate the intensity of phagocytosis, while large doses decrease phagocytic activity and produce cytotoxic effect. Yersinia LPS plays an important role in the development of such consequences of yersiniosis as reactive arthritis, erythema nodosum, Reiter's syndrome. Yersinia LPS is a widespread component for the diagnostics of yersiniosis and pseudotuberculosis. |