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dc.creatorFenn, T. D.en
dc.creatorSchnieders, M. J.en
dc.date.accessioned2015-09-09T15:50:21Zen
dc.date.available2015-09-09T15:50:21Zen
dc.date.issued2011-11en
dc.identifier.citationFenn, T. D., Michael Schnieders. >Polarizable atomic multipole X-ray refinement: weighting schemes for macromolecular diffraction,> Acta Cryst. (2011). D67, 957-965. doi:10.1107/S0907444911039060en
dc.identifier.issn0907-4449en
dc.identifier.urihttp://hdl.handle.net/2152/31075en
dc.description.abstractIn the past, weighting between the sum of chemical and data-based targets in macromolecular crystallographic refinement was based on comparing the gradients or Hessian diagonal terms of the two potential functions. Here, limitations of this scheme are demonstrated, especially in the context of a maximum-likelihood target that is inherently weighted by the model and data errors. In fact, the congruence between the maximum-likelihood target and a chemical potential based on polarizable atomic multipole electrostatics evaluated with Ewald summation has opened the door to a transferable static weight. An optimal static weight is derived from first principles and is demonstrated to be transferable across a broad range of data resolutions in the context of a recent implementation of X-ray crystallographic refinement using the polarizable AMOEBA force field and it is shown that the resulting models are balanced with respect to optimizing both R-free and MolProbity scores. Conversely, the classical automatic weighting scheme is shown to lead to underfitting or overfitting of the data and poor model geometry. The benefits of this approach for low-resolution diffraction data, where the need for prior chemical information is of particular importance, are also highlighted. It is demonstrated that this method is transferable between low-and high-resolution maximum-likelihood-based crystallographic refinement, which proves for the first time that resolution-dependent parameterization of either the weight or the chemical potential is unnecessary.en
dc.description.sponsorshipen
dc.language.isoEnglishen
dc.rightsAdministrative deposit of works to Texas ScholarWorks: This works author(s) is or was a University faculty member, student or staff member; this article is already available through open access or the publisher allows a PDF version of the article to be freely posted online. The library makes the deposit as a matter of fair use (for scholarly, educational, and research purposes), and to preserve the work and further secure public access to the works of the University.en
dc.subjectparticle mesh ewalden
dc.subjectcrystallographic refinementen
dc.subjectprotein structuresen
dc.subjecthydrogen-bondsen
dc.subjectcrystal-structuresen
dc.subjectforce-fieldsen
dc.subjectwater modelen
dc.subjectbeta-sheetsen
dc.subjectr-factoren
dc.subjectlikelihooden
dc.subjectbiochemical research methodsen
dc.subjectbiochemistry & molecular biologyen
dc.subjectbiophysicsen
dc.subjectcrystallographyen
dc.titlePolarizable Atomic Multipole X-Ray Refinement: Weighting Schemes For Macromolecular Diffractionen
dc.typeArticleen
dc.rights.holderen
dc.description.departmentMolecular Biosciencesen
dc.identifier.doi10.1107/s0907444911039060en
dc.identifier.urlen
dc.contributor.utaustinauthorSchnieders, M. J.en
dc.relation.ispartofserialActa Crystallographica Section D-Biological Crystallographyen


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