%0 Journal Article %T SAS profile correlations reveal SAS hierarchical nature and information content %+ Bioinformatique structurale - Structural Bioinformatics %A Spill, Yannick G. %A Nilges, Michael %Z This work was funded by the European Research Commission (Advanced Grant ERC-2011-StG 294809 BayCellS, to MN). %< avec comité de lecture %@ 1932-6203 %J PLoS ONE %I Public Library of Science %V 12 %N 5 %P e0177309 %8 2017-05-11 %D 2017 %R 10.1371/journal.pone.0177309 %M 28493950 %K Covariance %K Molecular dynamics %K Intrinsically disordered proteins %K Simulation and modeling %K Anisotropy %K Normal distribution %K Probability density %K Solvation %Z Life Sciences [q-bio] %Z Life Sciences [q-bio]/Biochemistry, Molecular Biology %Z Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM]Journal articles %X In structural biology, Small-Angle Scattering experiments (SAS) are unique, because although they provide low resolution data, they can be performed in closer-to-native conditions than those arising in X-Ray crystallography. A number of questions on SAS, however, remain unsolved, particularly in the light of modelling ensembles of conformers in solution. In this article, we study the ensemble average and covariance of SAS profiles analytically. Using this ensemble covariance, we demonstrate the hierarchical nature of SAS profiles. Furthermore, we show that the information content is not uniform and reaches its maximum in the intermediate q range. The arguments are generalized using microsecond-scale molecular dynamics trajectories of the lysozyme and on an ensemble of the intrinsically disordered protein p15PAF. We show that for highly flexible systems, the SAS profile is a representation of the ensemble of conformers in solution, and not that of one conformer in particular. %G English %Z YGS would like to acknowledge Dominique Durand, Patrice Vachette and Frédéric Poitevin for fruitful discussion and proofreading of the manuscript, Jochen S. Hub for sharing the lysozyme simulations, and Pau Bernadó for discussion on extension to IDPs. %2 https://pasteur.hal.science/pasteur-01570231/document %2 https://pasteur.hal.science/pasteur-01570231/file/journal.pone.0177309.pdf %L pasteur-01570231 %U https://pasteur.hal.science/pasteur-01570231 %~ PASTEUR %~ CNRS %~ OPENAIRE