Grant: Project Grant

Campylobacter jejuni (Cj) is a leading cause of bacterial food poisoning in humans in the developed world. Yet, it lives harmlessly in the intestinal tract of birds, with up to 90% of commercial poultry products having live Cj on their surfaces. Furthermore, unlike most other prevalent pathogens, its specific pathogenic mechanisms have remained elusive. Through genetic and computer-based screening, we have uncovered several new factors and means by which this pathogen is so successful in causing human disease, colonizing non-susceptible (commensal) hosts, and surviving in the environment outside of a host. One is its shape. Cj typically has a helical/corkscrew morphology, and this abets its ability to burrow into the intestinal mucosa of both susceptible (i.e., human) and commensal (i.e., poultry) hosts and to survive in inhospitable environments such as air and water. Changes to this shape alter Cj's ability to succeed in specific niches. Our group has identified the first bacterial factors and biochemical characteristics important for maintaining Cj's helical cell morphology. All of these affect the peptidoglycan layer of the bacterial cell wall. We will use genetic, biochemical, and other approaches to further our understanding of how shape is determined and maintained in Cj, and the biological and pathogenic implications of Cj morphology. Given the importance of Cj shape to its success as a pathogen, this work should provide important insights into Cj biology, how and why Cj is such a prevalent cause of human disease, and clues to its eradication.