Interpretation of very low resolution X-ray electron-density maps using core objects
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Updated: Jun 22, 2026

Enhancing Density Maps by Removing the Majority of Particles in Single Particle Cryogenic Electron Microscopy Final Stacks
Published on: May 10, 2024
Philipp Heuser1, Gerrit G Langer, Victor S Lamzin
1Hamburg Unit, European Molecular Biology Laboratory, c/o DESY, Notkestrasse 85, Hamburg 22603, Germany. philipp.heuser@embl-hamburg.de
Abstract:
A novel approach to obtaining structural information from macromolecular X-ray data extending to resolutions as low as 20 A is presented. Following a simple map-segmentation procedure, the approximate shapes of the domains forming the structure are identified. A pattern-recognition comparative analysis of these shapes and those derived from the structures of domains from the PDB results in candidate structural models that can be used for a fit into the density map. It is shown that the placed candidate models can be employed for subsequent phase extension to higher resolution.
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