X-ray radiation induces deprotonation of the bilin chromophore in crystalline D. radiodurans phytochrome.
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ABSTRACT:
SUBMITTER: Li F
PROVIDER: S-EPMC5660918 | biostudies-literature | 2015 Mar
REPOSITORIES: biostudies-literature
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X-ray radiation induces deprotonation of the bilin chromophore in crystalline D. radiodurans phytochrome.
Li Feifei F Burgie E Sethe ES Yu Tao T Héroux Annie A Schatz George C GC Vierstra Richard D RD Orville Allen M AM
Journal of the American Chemical Society 20150218 8
We report that in the red light-absorbing (Pr) state, the bilin chromophore of the Deinococcus radiodurans proteobacterial phytochrome (DrBphP) is hypersensitive to X-ray photons used in typical synchrotron X-ray protein crystallography experiments. This causes the otherwise fully protonated chromophore to deprotonate without additional major structural changes. These results have major implications for our understanding of the structural and chemical characteristics of the resting and intermedi ...[more]
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