Open AccessProtein crystallography with a micrometre‐sized synchrotron‐radiation beam
Author(s) -
Moukhametzianov Rouslan,
Burghammer Manfred,
Edwards Patricia C.,
Petitdemange Sebastien,
Popov Dimitri,
Fransen Maikel,
McMullan Gregory,
Schertler Gebhard F. X.,
Riekel Christian
Publication year - 2008
Publication title -
acta crystallographica section d
Language(s) - English
Resource type - Journals
ISSN - 1399-0047
DOI - 10.1107/s090744490705812x
Subject(s) - diffraction , synchrotron radiation , resolution (logic) , crystallite , materials science , synchrotron , irradiation , goniometer , radiation damage , optics , radiation , photon , beam (structure) , crystal (programming language) , protein crystallization , image resolution , crystallography , chemistry , physics , nuclear physics , computer science , programming language , artificial intelligence , organic chemistry , crystallization
For the first time, protein microcrystallography has been performed with a focused synchrotron‐radiation beam of 1 µm using a goniometer with a sub‐micrometre sphere of confusion. The crystal structure of xylanase II has been determined with a flux density of about 3 × 10 10 photons s −1 µm −2 at the sample. Two sets of diffraction images collected from different sized crystals were shown to comprise data of good quality, which allowed a 1.5 Å resolution xylanase II structure to be obtained. The main conclusion of this experiment is that a high‐resolution diffraction pattern can be obtained from 20 µm 3 crystal volume, corresponding to about 2 × 10 8 unit cells. Despite the high irradiation dose in this case, it was possible to obtain an excellent high‐resolution map and it could be concluded from the individual atomic B ‐factor patterns that there was no evidence of significant radiation damage. The photoelectron escape from a narrow diffraction channel is a possible reason for reduced radiation damage as indicated by Monte Carlo simulations. These results open many new opportunities in scanning protein microcrystallography and make random data collection from microcrystals a real possibility, therefore enabling structures to be solved from much smaller crystals than previously anticipated as long as the crystallites are well ordered.