Three-Dimensional Cubic Mesoporous Structures of SBA-12 and Related Materials by Electron Crystallography

2002 ◽  
Vol 106 (12) ◽  
pp. 3118-3123 ◽  
Author(s):  
Yasuhiro Sakamoto ◽  
Isabel Díaz ◽  
Osamu Terasaki ◽  
Dongyuan Zhao ◽  
Joaquin Pérez-Pariente ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Electron Crystallography ◽  
Cubic Mesoporous ◽  
Mesoporous Structures

Defocus ramp correction in spot-scan imaging

1992 ◽  
Vol 50 (1) ◽  
pp. 130-131
Author(s):  
Kenneth H. Downing
Keyword(s):  
Computer Control ◽  
Three Dimensional ◽  
Sufficient Accuracy ◽  
Objective Lens ◽  
Electron Crystallography ◽  
Contrast Transfer Function ◽  
Tilt Axis ◽  
Specimen Height ◽  
The Difference ◽  
Envelope Functions

Three-dimensional structures of a number of samples have been determined by electron crystallography. The procedures used in this work include recording images of fairly large areas of a specimen at high tilt angles. There is then a large defocus ramp across the image, and parts of the image are far out of focus. In the regions where the defocus is large, the contrast transfer function (CTF) varies rapidly across the image, especially at high resolution. Not only is the CTF then difficult to determine with sufficient accuracy to correct properly, but the image contrast is reduced by envelope functions which tend toward a low value at high defocus.We have combined computer control of the electron microscope with spot-scan imaging in order to eliminate most of the defocus ramp and its effects in the images of tilted specimens. In recording the spot-scan image, the beam is scanned along rows that are parallel to the tilt axis, so that along each row of spots the focus is constant. Between scan rows, the objective lens current is changed to correct for the difference in specimen height from one scan to the next.

scholarly journals Structure of catalase determined by MicroED

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Brent L Nannenga ◽  
Dan Shi ◽  
Johan Hattne ◽  
Francis E Reyes ◽  
Tamir Gonen
Keyword(s):  
Structure Determination ◽  
Three Dimensional ◽  
Bovine Liver ◽  
Electron Crystallography ◽  
X Ray ◽  
X Ray Crystallography ◽  
Continuous Rotation ◽  
Bovine Liver Catalase ◽  
Diffraction Patterns ◽  
Atomic Analysis

MicroED is a recently developed method that uses electron diffraction for structure determination from very small three-dimensional crystals of biological material. Previously we used a series of still diffraction patterns to determine the structure of lysozyme at 2.9 Å resolution with MicroED (<xref ref-type="bibr" rid="bib26">Shi et al., 2013</xref>). Here we present the structure of bovine liver catalase determined from a single crystal at 3.2 Å resolution by MicroED. The data were collected by continuous rotation of the sample under constant exposure and were processed and refined using standard programs for X-ray crystallography. The ability of MicroED to determine the structure of bovine liver catalase, a protein that has long resisted atomic analysis by traditional electron crystallography, demonstrates the potential of this method for structure determination.

Three-Dimensional Structure of F1-ATPase of Thermophilic Bacterium PS3 Obtained by Electron Crystallography

1993 ◽  
Vol 113 (2) ◽  
pp. 245-250 ◽  
Author(s):  
Noriyuki Ishii ◽  
Hideyuki Yoshimura ◽  
Kuniaki Nagayama ◽  
Yasuo Kagawa ◽  
Masasuke Yoshida
Keyword(s):  
Three Dimensional ◽  
Thermophilic Bacterium ◽  
Dimensional Structure ◽  
Electron Crystallography ◽  
Three Dimensional Structure ◽  
F1 Atpase
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