Direct phasing in femtosecond nanocrystallography. I. Diffraction characteristics
Category
Published on
Type
journal-article
Author
Joe P. J. Chen and John C. H. Spence and Rick P. Millane
Citation
Chen, J.P.J., Spence, J.C.H. & Millane, R.P., 2014. Direct phasing in femtosecond nanocrystallography. I. Diffraction characteristics. Acta Cryst Sect A Found Adv, 70(2), pp.143–153. Available at: http://dx.doi.org/10.1107/s2053273313032038.
Abstract
X-ray free-electron lasers solve a number of difficulties in protein crystallography by providing intense but ultra-short pulses of X-rays, allowing collection of useful diffraction data from nanocrystals. Whereas the diffraction from large crystals corresponds only to samples of the Fourier amplitude of the molecular transform at the Bragg peaks, diffraction from very small crystals allows measurement of the diffraction amplitudes between the Bragg samples. Although highly attenuated, these additional samples offer the possibility of iterative phase retrieval without the use of ancillary experimental data [Spenceet al.(2011).Opt. Express,19, 2866–2873]. This first of a series of two papers examines in detail the characteristics of diffraction patterns from collections of nanocrystals, estimation of the molecular transform and the noise characteristics of the measurements. The second paper [Chenet al.(2014).Acta Cryst.A70, 154–161] examines iterative phase-retrieval methods for reconstructing molecular structures in the presence of the variable noise levels in such data.
DOI
Funding
NSF-STC Biology with X-ray Lasers (NSF-1231306)
