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Deducing fast electron density changes in randomly orientated uncrystallized biomolecules in a pump–probe experiment

We propose a method for deducing time-resolved structural changes in uncrystallized biomolecules in solution. The method relies on measuring the angular correlations of the intensities, when averaged over a large number of diffraction patterns from randomly oriented biomolecules in solution in a liq...

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Detalles Bibliográficos
Autores principales: Pande, K., Schwander, P., Schmidt, M., Saldin, D. K.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4052868/
https://www.ncbi.nlm.nih.gov/pubmed/24914159
http://dx.doi.org/10.1098/rstb.2013.0332
Descripción
Sumario:We propose a method for deducing time-resolved structural changes in uncrystallized biomolecules in solution. The method relies on measuring the angular correlations of the intensities, when averaged over a large number of diffraction patterns from randomly oriented biomolecules in solution in a liquid solvent. The experiment is somewhat like a pump–probe version of an experiment on small angle X-ray scattering, except that the data expected by the algorithm are not just the radial variation of the averaged intensities. The differences of these correlation functions as measured from a photoexcited and dark structure enable the direct calculation of the difference electron density with a knowledge of only the dark structure. We exploit a linear relation we derive between the difference in these correlation functions and the difference electron density, applicable for small structural changes.