Phenix Wizards -- Automation of the Structure Determination Process
Tom Terwilliger

The PHENIX Wizards allow automation of major steps in the structure determination process. The Wizards carry out decision-making, provide suggestions for the user, and form a flexible environment for investigating alternative strategies for structure determination.

New algorithms available in PHENIX include a Iterative-build OMIT procedure for prevention of model bias and ligand identification in electron density maps. The PHENIX AutoBuild Wizard can carry out iterative model-building, density modification and refinement to improve the quality of models at resolutions as low as 3 A. Electron density maps calculated using an atomic model can be affected by model bias introduced during refinement of the model. We have developed a Iterative-build OMIT procedure that prevents model bias in iterative procedures for model-building and refinement while producing a high-quality electron-density map. The PHENIX LigandFit automated ligand-fitting Wizard can fit flexible ligands into an electron density map. The Wizard can identify unknown ligands by comparing a set of potential ligands to the map and finding the one that fits the density most closely.