Antigenic and phenotypic modifications of Yersinia pestis under calcium and glucose concentrations simulating the mammalian bloodstream environment.

To study the possible mechanism of extracellular resistance to phagocytes developed by Yersinia pestis in the early stage of plague infection, the behaviour of two Y. pestis strains, the vaccine EV-76 and fully virulent 231 (LD(50), 10 c.f.