title: Protein structure determination by single-wavelength anomalous diffraction phasing of X-ray free-electron laser data.
abstract: Serial femtosecond crystallography (SFX) at X-ray free-electron lasers (XFELs) offers unprecedented possibilities for macromolecular structure determination of systems that are prone to radiation damage. However, phasing XFEL data de novo is complicated by the inherent inaccuracy of SFX data, and only a few successful examples, mostly based on exceedingly strong anomalous or isomorphous difference signals, have been reported. Here, it is shown that SFX data from thaumatin microcrystals can be successfully phased using only the weak anomalous scattering from the endogenous S atoms. Moreover, a step-by-step investigation is presented of the particular problems of SAD phasing of SFX data, analysing data from a derivative with a strong anomalous signal as well as the weak signal from endogenous S atoms.
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, 69120 Heidelberg, Germany.
authors.forename: Karol
authors.initials: K
authors.lastname: Nass
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, 69120 Heidelberg, Germany.
authors.forename: Anton
authors.initials: A
authors.lastname: Meinhart
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, 69120 Heidelberg, Germany.
authors.forename: Thomas R M
authors.initials: TR
authors.lastname: Barends
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, 69120 Heidelberg, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Foucar
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, 69120 Heidelberg, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Gorel
authors.affiliation: European XFEL GmbH , Albert-Einstein-Ring 19, 22761 Hamburg, Germany.
authors.forename: Andrew
authors.initials: A
authors.lastname: Aquila
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, 69120 Heidelberg, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Botha
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, 69120 Heidelberg, Germany.
authors.forename: R Bruce
authors.initials: RB
authors.lastname: Doak
authors.affiliation: SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, CA 94025, USA.
authors.forename: Jason
authors.initials: J
authors.lastname: Koglin
authors.affiliation: SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, CA 94025, USA.
authors.forename: Mengning
authors.initials: M
authors.lastname: Liang
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, 69120 Heidelberg, Germany.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Shoeman
authors.affiliation: SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, CA 94025, USA.
authors.forename: Garth
authors.initials: G
authors.lastname: Williams
authors.affiliation: SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, CA 94025, USA.
authors.forename: Sebastien
authors.initials: S
authors.lastname: Boutet
authors.affiliation: Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research , Jahnstrasse 29, 69120 Heidelberg, Germany.
authors.forename: Ilme
authors.initials: I
authors.lastname: Schlichting
keywords: SAD phasing; SFX; X-ray free-electron lasers; XFELs; serial femtosecond crystallography; single-wavelength anomalous diffraction