A multi-model approach to assessing local and global cryo-EM map quality
Category
Published on
Type
posted-content
Author
Mark A Herzik and James Fraser and Gabriel C Lander
Citation
Herzik, M.A., Fraser, J. & Lander, G.C., 2017. A multi-model approach to assessing local and global cryo-EM map quality. Available at: http://dx.doi.org/10.1101/128561.
Abstract
There does not currently exist a standardized indicator of how well a cryo-EM-derived model represents the density from which it was generated. We present a straightforward methodology that utilizes freely available tools to generate a suite of independent models and to evaluate their convergence in an EM density. These analyses provide both a quantitative and qualitative assessment of the precision of the models and their representation of the density, respectively, while concurrently providing a platform for assessing both global and local EM map quality. We further use standardized datasets to provide an expected model-model agreement criterion for EM maps reported to be at 5 Å resolution or better. Associating multiple atomic models with a deposited EM map provides a rapid and accessible reporter of convergence, a strong indicator of highly resolved molecular detail, and is an important step toward an FSC-independent assessment of map and model quality.
DOI
Funding
NSF-STC Biology with X-ray Lasers (NSF-1231306)
