VIRULENCE FACTORS OF YERSINIA PESTIS AND FEATURES OF PATHOGENESIS
Abstract
The human pathogens Yersinia pseudotuberculosis and Yersinia enterocolitica cause enterocolitis, while Yersinia pestis is responsible for pneumonic, bubonic, and septicaemic plague. All three share an infection strategy that relies on a virulence factor arsenal to enable them to enter, adhere to, and colonise the host while evading host defences to avoid untimely clearance. Their arsenal includes a number of adhesins that allow the invading pathogens to establish a foothold in the host and to adhere to specific tissues later during infection. When the host innate immune system has been activated, all three pathogens produce a structure analogous to a hypodermic needle. This article analyzes the virulence factors and pathogenic mechanisms of Yersinia pestis. Y. pestis is the causative agent of plague, and its high pathogenicity is determined by the coordinated activity of several molecular factors. The article highlights the role of the Type III secretion system (T3SS), F1 antigen, Pla protease, V antigen, and siderophores in the pathogenesis of the disease. In addition, the mechanisms by which the bacterium suppresses the immune system, its survival strategies inside and outside host cells, and the pathophysiological basis of the lymphatic, septicemic, and pneumonic forms of plague are analyzed based on scientific literature.