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Updated: Aug 20, 2026

Online Size-exclusion and Ion-exchange Chromatography on a SAXS Beamline
Published on: January 5, 2017
The Uppsala Electron-Density Server
Gerard J Kleywegt1, Mark R Harris, Jin Yu Zou
1Department of Cell and Molecular Biology, Uppsala University, Biomedical Centre, Box 596, SE-751 24 Uppsala, Sweden. gerard@xray.bmc.uu.se
Abstract:
The Uppsala Electron Density Server (EDS; http://eds.bmc.uu.se/) is a web-based facility that provides access to electron-density maps and statistics concerning the fit of crystal structures and their maps. Maps are available for approximately 87% of the crystallographic Protein Data Bank (PDB) entries for which structure factors have been deposited and for which straightforward map calculations succeed in reproducing the published R value to within five percentage points. Here, an account is provided of the methods that are used to generate the information contained in the server. Some of the problems that are encountered in the map-generation process as well as some spin-offs of the project are also discussed.
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