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Time-resolved dimerization of a PAS-LOV protein measured with photocoupled small angle X-ray scattering.

ABSTRACT: Time-resolved small-angle X-ray scattering (SAXS) has been used to probe photoexcitation of the blue-light signal transduction protein Vivid (VVD). Laser excitation of sample in a continuous flow cell enables time-resolved measurement of the initial response of VVD to illumination. Good signal-to-noise is achieved without relying on multiple exposures of the same sample or limiting exposure times to prevent radiation damage. The SAXS data demonstrate that VVD dimerizes within tens of milliseconds of light-state activation. Time-resolved SAXS in a flow cell format is a general method for connecting chemical changes in photoreceptors to conformationally driven output signals.

SUBMITTER: Lamb JS

PROVIDER: S-EPMC2743002 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

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Time-resolved dimerization of a PAS-LOV protein measured with photocoupled small angle X-ray scattering.

Lamb Jessica S JS Zoltowski Brian D BD Pabit Suzette A SA Crane Brian R BR Pollack Lois L

Journal of the American Chemical Society 20080821 37

Time-resolved small-angle X-ray scattering (SAXS) has been used to probe photoexcitation of the blue-light signal transduction protein Vivid (VVD). Laser excitation of sample in a continuous flow cell enables time-resolved measurement of the initial response of VVD to illumination. Good signal-to-noise is achieved without relying on multiple exposures of the same sample or limiting exposure times to prevent radiation damage. The SAXS data demonstrate that VVD dimerizes within tens of millisecond ...[more]

PMID: 18715002

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