Protein crystallography: development of new methods and application to the study of pathogenesis. (360G-Wellcome-050211_Z_97_B)

I propose to conduct research in two areas of protein crystallography: the determination of crystal structures of medically-relevant proteins, and the development of theory and methods. The general focus of my group is on structures of potential drug or vaccine targets, which aid the development of new therapies. The proteins we are studying include several bacterial virulence factors. Structural studies of pertussis toxin are building a basis for the design of whooping cough vaccines. The structures of cell-binding B-subunits of E. coli Shiga-like toxin are allowing the cyclical design of improved ligands, which can be used as drugs to adsorb the toxin in the gut before it acts. The mechanism by which enteropathogenic E. coli adhere to the intestinal epithelium will be studied by determining the structure of EaeB. Other structural studies involve the serpin family of serine proteinase inhibitors and related proteins. A major goal is to clarify serpin mechanism by determining the structure of a complex with a proteinase. As well, the structure of plasminogen activator inhibitor-1 will be determined in its active state, followed by complexes with potential thrombolytic drugs. I have also begun to initiate new collaborations with other proposed members of the Institute. In crystallographic theory, I will continue to work on structure factor probability distributions, which have led to improved electron density maps and more powerful structure refinement. The power of these methods will be increased by generalising the probability distributions, and their application will be extended to the technique of density modification.