Milestones in electron crystallography

Abstract

SummaryElectron crystallography determines the structure of membrane embedded proteins in the twodimensionally crystallized state by cryo-transmission electron microscopy imaging and computer structure reconstruction. Milestones on the path to the structure are high-level expression, purification of functional protein, reconstitution into two-dimensional lipid membrane crystals, high-resolution imaging, and structure determination by computer image processing. Here we review the current state of these methods. We also created an Internet information exchange platform for electron crystallography, where guidelines for the imaging and data processing method are maintained. The server (http://2dx.org) provides the electron crystallography community with a central information exchange platform, which is structured in blog and Wiki form, allowing visitors to add comments or discussions. It currently offers a detailed step-by-step introduction to image processing with the MRC software program. The server is also a repository for the 2dx software package, a user-friendly image processing system for 2D membrane protein crystals.

Challenges and Opportunities for Biomimetic Membranes

“…The possibility of obtaining a high density of functional membrane proteins in BCP membranes has signiicant implications for applications of such systems. High level of protein packing density has been shown in lipid bilayers of protein-based membrane protein, using 2D crystallization [13][14][15] and several native membranes described earlier [13,16,17]. A more comprehensive understanding and characterization of membrane protein-BCP compatibility will also assist in making highly packed aquaporin-based membranes, similar to lipid-based membrane protein 2D crystals.…”

Vertebrate Membrane Proteins: Structure, Function, and Insights from Biophysical Approaches

“…Electron crystallography in principle allows the building of atomic models, not only for these proteins but also for their surrounding lipid bilayers. This analysis further allows better descriptions of lipid-protein interactions (reviewed in Renault et al, 2006) than are possible from X-ray crystallography. However, electron crystallography has its own limitations and should be viewed as an important complement and only in some case superior to X-ray crystallography.…”

Electron crystallography: imaging and single-crystal diffraction from powders

“…For electron crystallography studies of organic crystals and proteins, we refer to recent reviews by Dorset (1998Dorset ( , 2007 and Renault et al (2006). Surface structure analysis by electron crystallography was reviewed by Leslie et al (1999).…”