PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 3775965

Methods for specimen thickness determination in electron microscopy. II. Changes in thickness with dose.

J Berriman·K R Leonard
View original source ↗Export metadata ↓

Abstract

The electron diffraction patterns of tilted thin crystals were used to determine the unit cell size in the direction normal to the supporting film. The method revealed a considerable dose-dependent thinning or shrinkage. Using a variety of specimens and stains, we found that this amounted to a 50% reduction in volume and could be attributable to two causes. Firstly, the specimen is held to the supporting film so that volume changes can only occur through changes in thickness. Secondly, the decrease in volume is associated with a dose-induced mass loss which is greatly suppressed at liquid nitrogen temperatures.

Explore related subjects

CrystallographyMicroscopy, ElectronProteinsRadiation DosageJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

J Berriman, K R Leonard. 1986. Methods for specimen thickness determination in electron microscopy. II. Changes in thickness with dose.. https://doi.org/10.1016/0304-3991(86)90095-1

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

The same but different: isomorphous methods for phasing and high-throughput ligand screening.

Isomorphous difference methods allow rapid and detailed visualization of localized changes in macromolecular structures, whether as a result of mutation or the binding of ligands. Practical aspects of isomorphous methods and differential crystallography are presented, particularly in their application to the phasing of new structures by multiple isomorphous replacement and the detection and characterization of ligand binding. Techniques for maintaining isomorphism between crystals to maximize the differential signal are covered, as are the computational steps involved in generating difference electron density maps. Frontier applications such as determining single-site ligand-binding affinities crystallographically, high-throughput screening of combinatorial compound libraries, in crystallo competition assays, and inferring protein function via exogenous ligand-binding screens are discussed.

Crystallography↗
PubMed2007

Crystallographic software: a sustainable resource for the community.

Virtually all software is constantly changing and evolving (and crystallographic software is no exception), which makes it nearly impossible to write a chapter that will remain current. In this chapter, we introduce CRYSTAL, a website (http://crystal.uvm.edu) where a comprehensive list of available crystallographic packages for each step of macromolecular structure determination will be maintained. Additionally, we provide links to books, journals, and a number of educational sites on crystallography. For each program/site included at CRYSTAL, a detailed description will include: the most current version, the authors, and appropriate operating systems to host the program. Links to download the programs, available tutorials, and references to cite when using the program/site are also provided.

Crystallography↗
PubMed2006

Architecture of fiber network: from understanding to engineering of molecular gels.

A new approach of engineering of molecular gels was established on the basis of a nucleation-initiated network formation mechanism. A variety of gel network structures can be obtained by regulating the starting temperature of the sol-gel transition. This enables us to tune the network from the spherulitic domains pattern to the extensively interconnected fibrillar network. As the consequence of fibrous network structure turning, desirable rheological and other in-use properties of the materials can be obtained accordingly. This approach of micro-/nanostructural fabrication may open up a new route for micro-/nanofunctional materials engineering in general.

Crystallography↗