Project Summary (Overall Center) Structural biology is a multidisciplinary research area that focuses on the important relationship between macromolecular structure and function. The Oklahoma Center of Biomedical Research Excellence (COBRE) in Structural Biology (OCSB) was established in 2012 with Phase 1 funding. The OCSB supports faculty research projects and two research core facilities on the OU-Norman and OU Health Sciences Center campuses for crystallization of macromolecules of biomedical importance, X-ray data collection, protein expression and purification and biophysical analysis. The overall objective of this Phase 3 application is to provide essential research support in the State of Oklahoma and the region in the form of shared core facilities, training and expertise in structural biology, and an open competitive pilot project program. The specific aims of this Phase 3 application are to: 1) Sustain and enhance the research cores established and developed in Phases 1 and 2 and facilitate their transition to self-sustaining cores and 2) Increase the critical mass of investigators in the field of structural biology in the State of Oklahoma by supporting researchers through a competitive pilot project program.