Towards phasing using high X-ray intensity

IUCrJ

Barty, A.¹  Boutet, S.²  Barends, T.R.M.²  Nanao, M.H.²  Galli, L.²  Botha, S.²  Nass, K.³  Chapman, H.N.³  Son, S.-K.⁴  Timneanu, N.⁵  Schlichting, I.⁶  Shoeman, R.L.⁶  Caleman, C.⁶  Santra, R.⁶  Doak, R.B.⁷  White, T.A.⁸ 

[1] Biomolecular Mechanisms, MPI for Medical Research, Jahnstrasse 29, Heidelberg, 69120, Germany;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;Department of Physics, University of Hamburg, Luruper Chaussee 149, Hamburg, 22761, Germany;EMBL, Grenoble Outstation, Rue Jules Horowitz 6, Grenoble, 38042, France;Max Planck Institute for Medical Research, Jahnstrasse 29, Heidelberg, 69120, Germany;SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, 94025, USA;The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, Hamburg, 22761, Germany

关键词: SERIAL FEMTOSECOND CRYSTALLOGRAPHY;    HIGH-INTENSITY PHASING;    RADIATION DAMAGE;    ELECTRONIC DAMAGE;    X-RAY FREE-ELECTRON LASERS;    HIGH XFEL DOSES;   

DOI  :  10.1107/S2052252515014049

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

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.

【 授权许可】

CC BY