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bioRxiv · 10.1101/128561

A multi-model approach to assessing local and global cryo-EM map quality

Herzik, M. A.·Fraser, J.·Lander, G. C.
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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 [A] 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.

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Herzik, M. A., Fraser, J., Lander, G. C.. 2017-04-19. A multi-model approach to assessing local and global cryo-EM map quality. https://doi.org/10.1101/128561

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