Silencing urease: A key evolutionary step that facilitated the adaptation of …

The arthropod-borne transmission route of Yersinia pestis, the bacterial agent of plague, is a recent evolutionary adaptation.Yersinia pseudotuberculosis, the closely related food-and waterborne enteric species from which Y. pestis diverged less than 6,400 y ago, exhibits significant oral toxicity to the flea vectors of plague,whereas Y. pestis does not. In this study, we identify the Yersinia …