We describe a method for performing time-resolved X-ray crystallographic experiments based on the Hadamard transform, in which time resolution is defined by the underlying periodicity of the probe pulse sequence, and signal/noise is greatly improved over that for the fastest pump-probe experiments depending on a single pulse. This approach should be applicable on standard synchrotron beamlines and will enable high-resolution measurements of protein and small-molecule structural dynamics. It is also applicable to other time-resolved measurements where a probe can be encoded, such as pump-probe spectroscopy.
Protein Data Bank
Protein Data Bank
B.A.Y. is supported by the Wellcome Trust 4-year PhD program “The Molecular Basis of Biological Mechanisms” 089312/Z/09/Z. This work was also supported by the EPSRC Award “Dynamic Structural Science at the Research Complex at Harwell” EP/I01974X/1 and by BBSRC Award BB/H001905/1. Diffraction data were collected on beamline I24 at Diamond Light Source under proposal nt5810. We thank Diamond Light Source and the staff of I24 for beamtime and support and D. Waterman (CCP4) for the SUMSUB code. We also thank P. Raithby, C. Wilson, J. Trincao, J. Christensen, M. Hamilton, E. Snell, T. Burnley, C. Wood and C. Ballard for useful discussions and critical reading of the manuscript.
This script takes a user defined set of images from multiple crystals and produces an integrated list of reflections using XDS. These data can then be scaled, merged and converted to structure factors using the CCP4 software suite.
This script takes a plain text file (with the format H K L F1 SIGF1 F2 SIGF2 ... Fn SIGFn), calculates the S-matrix and carries out the HATRX transform. It outputs a plain text file in the same format as the input data.
This script converts the output of 2_HATRX.py into a CCP4 format mtz file ready for further analysis using any standard crystallographic software package.
This script uses the sumsub routine to create HATRX encoded images from a series of CBF format images. It was used to create the HATRX images here to show proof of principle of the method. When the HATRX data are generated by detector or beam encoding this step is not required.