1ts7
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| , resolution 1.6Å | |||||||
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| Ligands: | |||||||
| Gene: | PYP (Halorhodospira halophila) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Structure of the pR cis wobble and pR E46Q intermediates from time-resolved Laue crystallography
OverviewOverview
Determining 3D intermediate structures during the biological action of proteins in real time under ambient conditions is essential for understanding how proteins function. Here we use time-resolved Laue crystallography to extract short-lived intermediate structures and thereby unveil signal transduction in the blue light photoreceptor photoactive yellow protein (PYP) from Halorhodospira halophila. By analyzing a comprehensive set of Laue data during the PYP photocycle (forty-seven time points from one nanosecond to one second), we track all atoms in PYP during its photocycle and directly observe how absorption of a blue light photon by its p-coumaric acid chromophore triggers a reversible photocycle. We identify a complex chemical mechanism characterized by five distinct structural intermediates. Structural changes at the chromophore in the early, red-shifted intermediates are transduced to the exterior of the protein in the late, blue-shifted intermediates through an initial "volume-conserving" isomerization of the chromophore and the progressive disruption of hydrogen bonds between the chromophore and its surrounding binding pocket. These results yield a comprehensive view of the PYP photocycle when seen in the light of previous biophysical studies on the system.
About this StructureAbout this Structure
1TS7 is a Single protein structure of sequence from Halorhodospira halophila. Full crystallographic information is available from OCA.
ReferenceReference
Visualizing reaction pathways in photoactive yellow protein from nanoseconds to seconds., Ihee H, Rajagopal S, Srajer V, Pahl R, Anderson S, Schmidt M, Schotte F, Anfinrud PA, Wulff M, Moffat K, Proc Natl Acad Sci U S A. 2005 May 17;102(20):7145-50. Epub 2005 May 3. PMID:15870207
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