Forward and Reverse Genetics and the Evolution of Pathogens from Commensals
The human pathogens Bordetella pertussis and B. parapertussis appear to have emerged relatively recently as human pathogens. The disease they cause, pertussis, was THE major childhood killer in the US prior to an effective vaccine, and now infects tens of millions and kills hundreds of thousands annually. Genomic sequence data and experimental findings have shed light on the independent evolution of two distinct Bordetella subspecies from life-long commensals of a wide variety of animals to acute pathogens of humans. This adaptation is not the result of the acquisition of new virulence genes. Rather, the pathogens have LOST substantial fractions (15-25%) of the genome, including sets of genes that are critical to the success of strains referred to as the "progenitors" of the pathogens. How can a lineage that has LOST numerous "virulence" genes be more virulent? What is driving the evolution of the human pathogens? How might the rate of evolutionary change vary amongst different lineages? How can we use new tools and approaches to understand this ongoing process and the mechanisms that drive it?
Contact
Courtney C. Murdock
ccm15@psu.edu
814-865-1024