A maximum likelihood approach to two-dimensional crystals.
Details
Serval ID
serval:BIB_BADE0944AD06
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
A maximum likelihood approach to two-dimensional crystals.
Journal
Journal of structural biology
ISSN
1095-8657 (Electronic)
ISSN-L
1047-8477
Publication state
Published
Issued date
12/2007
Peer-reviewed
Oui
Volume
160
Number
3
Pages
362-374
Language
english
Notes
Publication types: Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
Publication Status: ppublish
Publication Status: ppublish
Abstract
Maximum likelihood (ML) processing of transmission electron microscopy images of protein particles can produce reconstructions of superior resolution due to a reduced reference bias. We have investigated a ML processing approach to images centered on the unit cells of two-dimensional (2D) crystal images. The implemented software makes use of the predictive lattice node tracking in the MRC software, which is used to window particle stacks. These are then noise-whitened and subjected to ML processing. Resulting ML maps are translated into amplitudes and phases for further processing within the 2dx software package. Compared with ML processing for randomly oriented single particles, the required computational costs are greatly reduced as the 2D crystals restrict the parameter search space. The software was applied to images of negatively stained or frozen hydrated 2D crystals of different crystal order. We find that the ML algorithm is not free from reference bias, even though its sensitivity to noise correlation is lower than for pure cross-correlation alignment. Compared with crystallographic processing, the newly developed software yields better resolution for 2D crystal images of lower crystal quality, and it performs equally well for well-ordered crystal images.
Keywords
Algorithms, Cryoelectron Microscopy/methods, Crystallization, Crystallography/methods, Fourier Analysis, Image Processing, Computer-Assisted/methods, Image Processing, Computer-Assisted/statistics & numerical data, Likelihood Functions, Microscopy, Electron, Transmission/methods, Negative Staining, Protein Conformation, Proteins/chemistry, Proteins/ultrastructure, Software
Pubmed
Web of science
Create date
09/06/2023 15:03
Last modification date
28/07/2023 5:59