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PubMed · 8248781

Photoactivated conformational changes in rhodopsin: a time-resolved spin label study.

Z T Farahbakhsh·K Hideg·W L Hubbell
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Abstract

Rhodopsin has been selectively spin-labeled near the cytoplasmic termini of helices C and G. Photoactivation with a light flash induces an electron paramagnetic resonance spectral change in the millisecond time domain, coincident with the appearance of the active metarhodopsin II intermediate. The spectral change is consistent with a small movement near the cytoplasmic termination of the C helix and reverses upon formation of the MIII state. These results provide an important link between the optical changes associated with the retinal chromophore and protein conformational states.

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Amino Acid SequenceElectron Spin Resonance SpectroscopyLightMolecular Sequence DataProtein ConformationProtein Structure, SecondaryRhodopsinSpin LabelsTemperatureJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Z T Farahbakhsh, K Hideg, W L Hubbell. 1993-11-26. Photoactivated conformational changes in rhodopsin: a time-resolved spin label study.. https://doi.org/10.1126/science.8248781

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