from Ali Navid and Eivind Almaas writing in Yersinia: Systems Biology and Control:
Bubonic plague is one of the deadliest diseases known to man. Unfortunately, despite all of our medical advances, we still do not have a working vaccine against this disease. Worse yet, discovery of anti-microbial resistant strains of Yersinia pestis, the causative agent of plague, could soon render our current therapeutic means ineffective. Unique characteristics of bacterial metabolism constitute one of the primary sets of targets for drug design. Accordingly, metabolism of Y. pestis has been one of the most studied aspects of its physiology.
Further reading: Yersinia: Systems Biology and Control