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Fast and accurate conversion of atomic models into electron density maps

1 National Center of Biotechnology (CSIC), c/Darwin, 3, Campus Univ. Autónoma de Madrid, 28049 Cantoblanco, Madrid, Spain;
2 Bioengineering Lab., Escuela Politécnica Superior, Univ. San Pablo CEU, Campus Urb. Montepríncipe s/n, 28668, Boadilla del Monte, Madrid, Spain;
3 Escuela Politécnica Superior, Univ. Autónoma de Madrid, Campus Univ. Autónoma de Madrid, 28049 Cantoblanco, Madrid, Spain

Special Issues: Structural analysis of macromolecules using Cryo electron microscopy

New image processing methodologies and algorithms have greatly contributed to the signi cant progress in three-dimensional electron microscopy (3DEM) of biological complexes we have seen over the last decades. Naturally, the availability of accurate procedures for the objective testing of new algorithms is a crucial requirement for the further advancement of the eld. A good and accepted testing work ow involves the generation of realistic 3DEM-like maps of biological macromolecules from which some measure of ground truth can be derived, ideally because their 3D atomic structure is already known. In this work we propose a very accurate generation of maps using atomic form factors for electron scattering. We thoroughly review current approaches in the eld, quantitatively demonstrating the bene ts of the new methodology. Additionally, we study a concrete example of the use of this approach for hypothesis testing in 3D Electron Microscopy.
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Copyright Info: © 2015, Carlos O.S. Sorzano, et al., licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution Licese (http://creativecommons.org/licenses/by/4.0)

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