Plastic-embedded protein crystals.

Raimond B G Ravelli; Uta Haselmann-Weiss; John E McGeehan; Andrew A McCarthy; Josan A Marquez; Claude Antony; Achilleas S Frangakis; Gudrun Stranzl

doi:10.1107/s0909049506043111

PubMed · 17211079

Plastic-embedded protein crystals.

Raimond B G Ravelli·Uta Haselmann-Weiss·John E McGeehan·Andrew A McCarthy·Josan A Marquez·Claude Antony·Achilleas S Frangakis·Gudrun Stranzl

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Abstract

Rapid vitrification followed by the replacement of the vitrified water by a solvent (freeze substitution) and then resin is a widely used procedure for preparing biological samples for electron microscopy. The resulting plastic-embedded samples permit convenient room-temperature sectioning (microtomy) and can yield well preserved cellular structures. Here this procedure has been applied to crystalline protein samples, and it is shown that it is possible to freeze-substitute vitrified crystals while preserving some of their original diffraction properties. The plastic-embedded crystals were used to collect a series of complete room-temperature data sets at a powerful macromolecular crystallography synchrotron beamline. Whereas one normally observes specific damage to disulfide bonds upon X-ray radiation, no such damage was seen for the plastic-embedded sample. The X-ray diffraction data allowed an initial atomic analysis to be made of the effects of freeze-substitution and plastic embedding on biological samples.

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Acrylic Resins Coated Materials, Biocompatible Computer Simulation Crystallization Dose-Response Relationship, Radiation Models, Chemical Models, Molecular Muramidase Plastic Embedding Protein Conformation Protein Denaturation Radiation Dosage Specimen Handling X-Ray Diffraction X-Rays Journal Article Research Support, Non-U.S. Gov't

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Raimond B G Ravelli, Uta Haselmann-Weiss, John E McGeehan, Andrew A McCarthy, Josan A Marquez, Claude Antony, Achilleas S Frangakis, Gudrun Stranzl. 2006-12-15. Plastic-embedded protein crystals.. https://doi.org/10.1107/s0909049506043111

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