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Updated: Jul 20, 2026

Application of Laser Micro-irradiation for Examination of Single and Double Strand Break Repair in Mammalian Cells
Published on: September 5, 2017
Specific radiation damage illustrates light-induced structural changes in the photosynthetic reaction center
Richard H G Baxter1, Brandon-Luke Seagle, Nina Ponomarenko
1Department of Chemistry, University of Chicago, 5735 South Ellis Avenue, Chicago, IL 60637, USA. r.baxter@alumni.uchicago.edu
Abstract:
The photosynthetic reaction center of the purple non-sulfur bacterium Blastochloris viridis was frozen in the presence and absence of illumination. Differences in the resulting datasets are monitored using the difference Fourier method. Radiation damage is localized to those parts of the protein that are significant for electron transfer, and show changes that are sensitive to oxidation and protonation state.
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