Project Summary (Biomolecular Structure Core) The analysis of the three-dimensional structures of proteins, nucleic acids, and their complexes provides unique insights into their biological function that are important for developing better therapeutics to prevent or treat human diseases. The Biomolecular Structure Core (BSC) provides expertise and state-of-the-art instrumentation for structure determination and analysis to support research groups affiliated with the Oklahoma COBRE in Structural Biology (OCSB) and other groups involved in structural biology research across the State of Oklahoma and in the region. The BSC accomplishes this purpose by using robotic instrumentation for the screening of crystallization conditions, high-flux microfocus X-ray generators, and a state-of-the-art hybrid pixel X-ray detector for rapid data collection along with computational resources to process and determine the structure of the macromolecule of interest. Dr. Blaine Mooers (Academic Core Director) and Dr. Leonard Thomas (Facility Manager) are full-time Ph.D. crystallographers. The core employs a Staff Scientist and a Graduate Assistant to aid in the screening of crystallization conditions and the preparation of samples for the collection of X-ray data. The core provides training to students, postdoctoral fellows, and faculty who are interested in macromolecular structure determination. The services of the BSC encompass all aspects of structure determination including crystallization screening, crystal cryo-protectant screening, diffraction data collection and processing, structure determination and refinement, structure analysis and interpretation, figure preparation, and structure deposition in the Protein Data Bank. The core also facilitates diffraction data collection at national synchrotron facilities. During Phase 2, a Molecular Modeling Unit was added to the core, which has been facilitating intensive computational work for candidate drug molecule screening, molecular dynamics simulations, and molecular replacement. This unit will also be used for molecular modeling with small-angle X-ray scattering studies (SAXS) data and cryo-EM data with ensembles of structures. During Phases 1 and 2 of OCSB funding, the BSC’s user base expanded from 7 to over 50 user groups. To promote further expansion of the user base in Phase 3, the BSC will expand its support and promotion of solution- based structure determination methodologies, such as SAXS and cryo-EM. The BSC Academic Core Director Dr. Blaine Mooers is a SAXS expert and thus uniquely qualified to consult and collaborate with researchers in need of this methodology. During Phase 2, OCSB funding was used to purchase cryo-plungers for the freezing of samples for cryo-EM. In addition, the University of Oklahoma recently hired a TEM specialist as a staff scientist for its OU Samuel Roberts Noble Microscopy Laboratory (SRNML) to allow for the expansion into cryo-EM. The core is collaborating with the SRNML on i...