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arXiv · 1611.08259

Solution X-ray scattering (S/WAXS) and structure formation in protein dynamics

Alexandr Nasedkin·Jan Davidsson·Antti J. Niemi·Xubiao Peng
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Abstract

We propose to develop mean field theory in combination with Glauber algorithm, to model and interpret protein dynamics and structure formation in small to wide angle x-ray scattering (S/WAXS) experiments. We develop the methodology by analysing the Engrailed homeodomain protein as an example. We demonstrate how to interpret S/WAXS data with a good precision and over an extended temperature range. We explain experimentally observed phenomena in terms of protein phase structure, and we make predictions for future experiments how the scattering data behaves at different ambient temperature values. We conclude that a combination of mean field theory with Glauber algorithm has the potential to develop into a highly accurate, computationally effective and predictive tool for analysing S/WAXS data. Finally, we compare our results with those obtained previously in an all-atom molecular dynamics simulation.

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Alexandr Nasedkin, Jan Davidsson, Antti J. Niemi, Xubiao Peng. 2017-06-05. Solution X-ray scattering (S/WAXS) and structure formation in protein dynamics. https://doi.org/10.1103/physreve.96.062405

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