Radioprotectant screening for cryocrystallography.

Robert J Southworth-Davies; Elspeth F Garman

doi:10.1107/s0909049506044177

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PubMed · 17211073

Radioprotectant screening for cryocrystallography.

Robert J Southworth-Davies·Elspeth F Garman

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Abstract

Radiation damage continues to present a problem to crystallographers using cryocooled protein crystals at third-generation synchrotrons. Free-radical scavengers have been suggested as a possible means of reducing the rate of this damage. The screening of a large number of potential radioprotectants was undertaken with an online microspectrophotometer using cystine and cysteine to model protein disulfide bonds and thiol groups, respectively. Oxidized alpha-lipoic acid was tested as a possible model disulfide bond. The evidence for the effectiveness of ascorbate as a radioprotectant was strengthened, and quinone, 2,2,6,6-tetramethyl-4-piperidone, and reduced dithiothreitol showed promise as radioprotectants.

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Computer Simulation Crystallography, X-Ray Dose-Response Relationship, Radiation Protein Conformation Protein Denaturation Proteins Radiation Dosage Radiation-Protective Agents X-Rays Journal Article Research Support, Non-U.S. Gov't

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Robert J Southworth-Davies, Elspeth F Garman. 2006-12-15. Radioprotectant screening for cryocrystallography.. https://doi.org/10.1107/s0909049506044177

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