Grant: Discovery Grants Program - Individual

Understanding the host range and virulence of bacterial pathogens is central to our ability to predict and control emerging and reemerging infectious diseases. For multi-host pathogens, which have evolved the ability to exploit both plants and animals, knowledge of their host range and disease strategies is critical to assessing their evolutionary momentum and potential for emergence. This work will involve a phylogenetic analysis of clinical and plant pathogenic isolates of Pantoea agglomerans to determine whether these isolates are closely related or form distinct evolutionary groups. Testing their pathogenicity in both plant and animal hosts will reveal their true host range, and whether plant isolates have the capacity to infect animals. This will be complemented by genetic screening to identify animal-specific virulence factors, which can then be used to identify whether a specific strain has the potential to become animal-pathogenic. Whole-genome comparisons of multiple P. agglomerans isolates along with an analysis of virulence gene distribution across all isolates will permit the reconstruction of the stepwise evolutionary events that have allowed this bacterial species to exploit both plant and animal hosts. As a genetically diverse multi-host pathogen, P. agglomerans not only provides the unique opportunity to study host-specific virulence determinants, but also the evolutionary forces contributing to the expansion and retraction of host range. This research has the potential to fundamentally alter our understanding of the evolutionary processes that govern host-specific virulence and disease, and the emergence of new infectious agents.