Probing anisotropic structure changes in proteins with picosecond time-resolved small-angle X-ray scattering.

ABSTRACT: We have exploited the principle of photoselection and the method of time-resolved small-angle X-ray scattering (SAXS) to investigate protein size and shape changes following photoactivation of photoactive yellow protein (PYP) in solution with ∼150 ps time resolution. This study partially overcomes the orientational average intrinsic to solution scattering methods and provides structural information at a higher level of detail. Photoactivation of the p-coumaric acid (pCA) chromophore in PYP produces a highly contorted, short-lived, red-shifted intermediate (pR0), and triggers prompt, protein compaction of approximately 0.3% along the direction defined by the electronic transition dipole moment of the chromophore. Contraction along this dimension is accompanied by expansion along the orthogo

SUBMITTER: Cho HS 

PROVIDER: S-EPMC4124878 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature