Towards phasing using high X-ray intensity

Lorenzo Galli; Sang-Kil Son; Thomas R M Barends; Thomas A White; Anton Barty; Sabine Botha; Sébastien Boutet; Carl Caleman; R Bruce Doak; Max H Nanao; Karol Nass; Robert L Shoeman; Nicusor Timneanu; Robin Santra; Ilme Schlichting; Henry N Chapman

doi:10.1107/S2052252515014049

Towards phasing using high X-ray intensity

IUCrJ. 2015 Sep 30;2(Pt 6):627-34. doi: 10.1107/S2052252515014049. eCollection 2015 Nov 1.

Authors

Lorenzo Galli¹, Sang-Kil Son², Thomas R M Barends³, Thomas A White⁴, Anton Barty⁴, Sabine Botha⁵, Sébastien Boutet⁶, Carl Caleman⁷, R Bruce Doak⁵, Max H Nanao⁸, Karol Nass⁵, Robert L Shoeman⁵, Nicusor Timneanu⁹, Robin Santra¹⁰, Ilme Schlichting⁵, Henry N Chapman¹¹

Affiliations

¹ Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY , Notkestrasse 85, Hamburg, 22607, Germany ; Department of Physics, University of Hamburg , Luruper Chaussee 149, Hamburg, 22761, Germany.
² Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY , Notkestrasse 85, Hamburg, 22607, Germany ; The Hamburg Centre for Ultrafast Imaging , Luruper Chaussee 149, Hamburg, 22761, Germany.
³ Biomolecular Mechanisms, MPI for Medical Research , Jahnstrasse 29, Heidelberg, 69120, Germany.
⁴ Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY , Notkestrasse 85, Hamburg, 22607, Germany.
⁵ Max Planck Institute for Medical Research , Jahnstrasse 29, Heidelberg, 69120, Germany.
⁶ SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, 94025, USA.
⁷ Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY , Notkestrasse 85, Hamburg, 22607, Germany ; Department of Physics and Astronomy, Uppsala University , Box 516, Uppsala, 75120, Sweden.
⁸ EMBL, Grenoble Outstation , Rue Jules Horowitz 6, Grenoble, 38042, France.
⁹ Department of Physics and Astronomy, Uppsala University , Box 516, Uppsala, 75120, Sweden ; Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University , Box 596, Uppsala, 75124, Sweden.
¹⁰ Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY , Notkestrasse 85, Hamburg, 22607, Germany ; The Hamburg Centre for Ultrafast Imaging , Luruper Chaussee 149, Hamburg, 22761, Germany ; Department of Physics, University of Hamburg , Juniungstrasse 6, Hamburg, 20355, Germany.
¹¹ Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY , Notkestrasse 85, Hamburg, 22607, Germany ; Department of Physics, University of Hamburg , Luruper Chaussee 149, Hamburg, 22761, Germany ; The Hamburg Centre for Ultrafast Imaging , Luruper Chaussee 149, Hamburg, 22761, Germany.

Abstract

X-ray free-electron lasers (XFELs) show great promise for macromolecular structure determination from sub-micrometre-sized crystals, using the emerging method of serial femtosecond crystallography. The extreme brightness of the XFEL radiation can multiply ionize most, if not all, atoms in a protein, causing their scattering factors to change during the pulse, with a preferential 'bleaching' of heavy atoms. This paper investigates the effects of electronic damage on experimental data collected from a Gd derivative of lysozyme microcrystals at different X-ray intensities, and the degree of ionization of Gd atoms is quantified from phased difference Fourier maps. A pattern sorting scheme is proposed to maximize the ionization contrast and the way in which the local electronic damage can be used for a new experimental phasing method is discussed.

Keywords: X-ray free-electron lasers; electronic damage; high XFEL doses; high-intensity phasing; radiation damage; serial femtosecond crystallography.

Abstract

Grants and funding