<i>ATSAS 2.8</i>: a comprehensive data analysis suite for small-angle scattering from macromolecular solutions

Abstract

<i>ATSAS</i> is a comprehensive software suite for the analysis of small-angle scattering data from dilute solutions of biological macromolecules or nanoparticles. It contains applications for primary data processing and assessment, <i>ab initio</i> bead modelling, and model validation, as well as methods for the analysis of flexibility and mixtures. In addition, approaches are supported that utilize information from X-ray crystallography, nuclear magnetic resonance spectroscopy or atomistic homology modelling to construct hybrid models based on the scattering data. This article summarizes the progress made during the 2.5-2.8 <i>ATSAS</i> release series and highlights the latest developments. These include <i>AMBIMETER</i>, an assessment of the reconstruction ambiguity of experimental data; <i>DATCLASS</i>, a multiclass shape classification based on experimental data; <i>SASRES</i>, for estimating the resolution of <i>ab initio</i> model reconstructions; <i>CHROMIXS</i>, a convenient interface to analyse in-line size exclusion chromatography data; <i>SHANUM</i>, to evaluate the useful angular range in measured data; <i>SREFLEX</i>, to refine available high-resolution models using normal mode analysis; <i>SUPALM</i> for a rapid superposition of low- and high-resolution models; and <i>SASPy</i>, the <i>ATSAS</i> plugin for interactive modelling in <i>PyMOL</i>. All these features and other improvements are included in the <i>ATSAS</i> release 2.8, freely available for academic users from https://www.embl-hamburg.de/biosaxs/software.html.