Resolution of ab initio shapes determined from small-angle scattering

Spatial resolution is an important characteristic of structural models, and the authors of structures determined by X-ray crystallography or electron cryo-microscopy always provide the resolution upon publication and deposition. Small-angle scattering of X-rays or neutrons (SAS) has recently become a mainstream structural method providing the overall three-dimensional structures of proteins, nucleic acids and complexes in solution. However, no quantitative resolution measure is available for SAS-derived models, which significantly hampers their validation and further use. Here, a method is derived for resolution assessment for ab initio shape reconstruction from scattering data. The inherent variability of the ab initio shapes is utilized and it is demonstrated how their average Fourier shell correlation function is related to the model resolution. The method is validated against simulated data for proteins with known high-resolution structures and its efficiency is demonstrated in applications to experimental data. It is proposed that henceforth the resolution be reported in publications and depositions of ab initio SAS models.

Abstract licence: CC BY

1. 26.

   A New Generation of Crystallographic Validation Tools for the Protein Data Bank · 2011

2. 27.

   DAMMIF , a program for rapid ab-initio shape determination in small-angle scattering · 2009

3. 29.

   Upgraded ESRF BM29 beamline for SAXS on macromolecules in solution · 2013

4. 31.

   Versatile sample environments and automation for biological solution X-ray scattering experiments at the P12 beamline (PETRA III, DESY) · 2015

5. 33.

   SCOPe: Structural Classification of Proteins—extended, integrating SCOP and ASTRAL data and classification of new structures · 2013

32 more references, whose wording the paper’s licence keeps private.

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• 2017 publication guidelines for structural modelling of small-angle scattering data from biomolecules in solution: an update · 2017

• ATSAS 2.8 : a comprehensive data analysis suite for small-angle scattering from macromolecular solutions · 2017

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