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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
1989-5-5
|
| pubmed:abstractText |
Two-dimensional crystals of bovine NADH: ubiquinone oxidoreductase fragments were studied by cryo-electron microscopy and computer image analysis at two focus settings. The lattice parameters of the crystals were determined as a = 14.5 +/- 0.2 nm, b = 14.8 +/- 0.3 nm with gamma = 87.8 degrees +/- 0.2 degrees. Translation and rotation alignment resulted in a final resolution of 1.38 (close-to-focus) or 1.9 nm (1.3 microns underfocus). When only translational alignment was employed 1.6 nm resolution resulted (close-to-focus case). The application of a further correction procedure surprisingly lowered the achieved resolution to 2.2 nm. A combination of the projected structures for the two focus settings in Fourier space resulted in a noise-free image displaying enhanced image contrast for reciprocal spacings from 1/5.0 to 1/1.4 nm-1. The structure in amorphous ice comprises four separate quasi-identical motifs, each resembling a distorted triangle. Two symmetry-related (p2) motifs reveal a pore-like feature. In negative stain the structure has p4mm symmetry. The absence of in-plane symmetry elements (i.e. twofold rotation and screw axes) and other differences might be accounted for (at least in part) if the crystal studied was slightly tilted.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:issn |
0304-3991
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
27
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
91-9
|
| pubmed:dateRevised |
2007-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:2467418-Animals,
pubmed-meshheading:2467418-Cattle,
pubmed-meshheading:2467418-Crystallization,
pubmed-meshheading:2467418-Freezing,
pubmed-meshheading:2467418-Image Processing, Computer-Assisted,
pubmed-meshheading:2467418-Microscopy, Electron,
pubmed-meshheading:2467418-Myocardium,
pubmed-meshheading:2467418-NAD(P)H Dehydrogenase (Quinone),
pubmed-meshheading:2467418-Quinone Reductases,
pubmed-meshheading:2467418-Staining and Labeling
|
| pubmed:articleTitle |
Computer image analysis of two-dimensional crystals of beef heart NADH: ubiquinone oxidoreductase fragments. II. Comparison of frozen hydrated and negatively stained specimens.
|
| pubmed:affiliation |
Biochemisch Laboratorium, Rijksuniversiteit Groningen, The Netherlands.
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|