Model-based local density sharpening of cryo-EM maps.

Autor: Jakobi AJ; Structural and Computational Biology, European Molecular Biology Laboratory, Heidelberg, Germany.; Hamburg Unit c/o DESY, European Molecular Biology Laboratory, Hamburg, Germany.; The Hamburg Centre for Ultrafast Imaging, Hamburg, Germany., Wilmanns M; Hamburg Unit c/o DESY, European Molecular Biology Laboratory, Hamburg, Germany., Sachse C; Structural and Computational Biology, European Molecular Biology Laboratory, Heidelberg, Germany.
Jazyk: angličtina
Zdroj: ELife [Elife] 2017 Oct 23; Vol. 6. Date of Electronic Publication: 2017 Oct 23.
DOI: 10.7554/eLife.27131
Abstrakt: Atomic models based on high-resolution density maps are the ultimate result of the cryo-EM structure determination process. Here, we introduce a general procedure for local sharpening of cryo-EM density maps based on prior knowledge of an atomic reference structure. The procedure optimizes contrast of cryo-EM densities by amplitude scaling against the radially averaged local falloff estimated from a windowed reference model. By testing the procedure using six cryo-EM structures of TRPV1, β-galactosidase, γ-secretase, ribosome-EF-Tu complex, 20S proteasome and RNA polymerase III, we illustrate how local sharpening can increase interpretability of density maps in particular in cases of resolution variation and facilitates model building and atomic model refinement.
Databáze: MEDLINE