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Tracking the structural dynamics of proteins in solution using time-resolved wide-angle X-ray scattering

An Erratum to this article was published on 01 November 2008

This article has been updated


We demonstrate tracking of protein structural changes with time-resolved wide-angle X-ray scattering (TR-WAXS) with nanosecond time resolution. We investigated the tertiary and quaternary conformational changes of human hemoglobin under nearly physiological conditions triggered by laser-induced ligand photolysis. We also report data on optically induced tertiary relaxations of myoglobin and refolding of cytochrome c to illustrate the wide applicability of the technique. By providing insights into the structural dynamics of proteins functioning in their natural environment, TR-WAXS complements and extends results obtained with time-resolved optical spectroscopy and X-ray crystallography.

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Figure 1: Plausibility of TR-WAXS based on photon statistics considerations.
Figure 2: TR-WAXS methodology and data processing.
Figure 3: TR-WAXS data on hemoglobin and the solvent heating contribution.
Figure 4: Comparison between TR-WAXS scattering differences and scattering differences calculated from crystallographic structures.
Figure 5: Application of TR-WAXS to track folding of Cyt-c.

Change history

  • 29 September 2008

    NOTE: In the version of this article initially published, the time scale reported in the Figure 2d legend is incorrect. The correct time scale should be 3 μs. Additionally, the time delay of 320 ms reported in Figure 5b is incorrect. The correct time delay is 200 ms. These errors have been corrected in the HTML and PDF versions of the article.


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We thank W.A. Eaton and E. Henry for helpful comments, H.-S. Cho and S. Ahn for helpful discussions about the data analysis, and Y.O. Jung, K.H. Kim and J.H. Lee for their assistance with sample preparation and experiments. This research was supported in part by the Intramural Research Program of the National Institutes of Health to P.A.A., by EU grant FLASH: FP6-503641 to M.W., and a grant from the Creative Research Initiatives (Center for Time-Resolved Diffraction) of the Ministry of Education, Science and Technology, Korea Science and Engineering Foundation to H.I.

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Correspondence to Marco Cammarata or Hyotcherl Ihee.

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Supplementary Figures 1–6, Supplementary Tables 1–4, Supplementary Methods (PDF 975 kb)

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Cammarata, M., Levantino, M., Schotte, F. et al. Tracking the structural dynamics of proteins in solution using time-resolved wide-angle X-ray scattering. Nat Methods 5, 881–886 (2008).

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