A bacterial pathogen's ability to infect hosts is frequently conferred by genes on mobile genetic elements called plasmids. These genetic elements sometimes spread through bacterial populations because of the competitive advantages they confer to the bacteria that harbor them. Plasmids can also decline in populations when their net effects are negative. A main goal of this project is to understand how ecological factors, such as resource levels, influence the maintenance of a disease-causing plasmid. The focal plasmid employs intercellular communication to coordinate a component of its spread.
A second goal of this project is to provide insight into the adaptive reasons many bacteria (and many pathogens) utilize communication. This project will combine experimental approaches with mathematical modeling to examine these issues.
Plasmids carry genes involved in many important functions, including pathogenesis and antibiotic resistance. However, because of the unique biology of plasmids, biologists do not fully understand their population dynamics. This project focuses on understanding the costs and benefits associated with maintaining a virulence plasmid in a common plant pathogen that is a frequent agricultural pest. As similar population dynamics occur in outbreaks of antibiotic resistant bacteria, this project could also inform a general understanding of the biology underlying this major public health problem.
