William Picking is a professor of Veterinary Pathobiology in the College of Veterinary Medicine

Picking investigates the molecules and structures used by pathogenic bacteria to cause disease in humans and animals.  His main focus is on specialized structures called type III secretion systems (T3SS) that pathogens such as Shigella, Salmonella and Pseudomonas use to communicate with host cells to alter their normal behavior for the benefit of the pathogen. 

For example, Shigella flexneri uses T3SS to promote uptake by the cells of the large intestine and then to escape into the cell’s cytoplasm, where this pathogen grows and spreads to neighboring cells.  The result is potentially severe bacillary dysentery, commonly seen around the world.  The T3SS “injectisome” literally resembles a syringe and needle and it is used to inject specialized proteins into target cells to alter the host’s normal cellular functions.  This work has revealed important information on how these nanomachines function uncovered targets that are laying the foundation for the development of future anti-infective agents and vaccines.