Open AccessNon‐rigid image registration to reduce beam‐induced blurring of cryo‐electron microscopy images
Author(s) -
Karimi Nejadasl Fatemeh,
Karuppasamy Manikandan,
Newman Emily R.,
McGeehan John E.,
Ravelli Raimond B. G.
Publication year - 2013
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049512044408
Subject(s) - fiducial marker , interpolation (computer graphics) , series (stratigraphy) , resolution (logic) , biological specimen , materials science , optics , electron microscope , computer vision , physics , chemistry , computer science , image (mathematics) , artificial intelligence , geology , paleontology
The typical dose used to record cryo‐electron microscopy images from vitrified biological specimens is so high that radiation‐induced structural alterations are bound to occur during data acquisition. Integration of all scattered electrons into one image can lead to significant blurring, particularly if the data are collected from an unsupported thin layer of ice suspended over the holes of a support film. Here, the dose has been fractioned and exposure series have been acquired in order to study beam‐induced specimen movements under low dose conditions, prior to bubbling. Gold particles were added to the protein sample as fiducial markers. These were automatically localized and tracked throughout the exposure series and showed correlated motions within small patches, with larger amplitudes of motion vectors at the start of a series compared with the end of each series. A non‐rigid scheme was used to register all images within each exposure series, using natural neighbor interpolation with the gold particles as anchor points. The procedure increases the contrast and resolution of the examined macromolecules.