Continuous improvement of macromolecular crystal structures

Thomas C. Terwilliger

Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545, USA


We propose that it is now feasible and desirable to develop mechanisms for continuous and systematic improvement of macromolecular crystal structures. It is feasible because of the availability of crystallographic data and the extensive automation of crystal structure determination and validation. It is desirable because small errors in interpretation can be fixed, improved methods for structure analysis can be applied, and groups of structures can be re-analyzed to extract maximal information about the set of structures. If raw diffraction data are deposited then the continuous improvement process can be more extensive than if only processed data are available, as raw diffraction data allows reprocessing of images, full confirmation of crystal symmetry, and even validation of the model using the original diffraction images. Key questions include how the various interpretations of a structure might be stored and how a user could find the most appropriate structure for their purposes.