9
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      The color of rhodopsins at the ab initio multiconfigurational perturbation theory resolution.

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          We demonstrate that "brute force" quantum-mechanics/molecular-mechanics computations based on ab initio (i.e., first principles) multiconfigurational perturbation theory can reproduce the absorption maxima of a set of modified bovine rhodopsins with an accuracy allowing for the analysis of the factors determining their colors. In particular, we show that the theory accounts for the changes in excitation energy even when the proteins display the same charge distribution. Three color-tuning mechanisms, leading to changes of close magnitude, are demonstrated to operate in these conditions. The first is based on the change of the conformation of the conjugated backbone of the retinal chromophore. The second operates through the control of the distance between the positive charge residing on the chromophore and the carboxylate counterion. Finally, the third mechanism operates through the changes in orientation of the chromophore relative to the protein. These results offer perspectives for the unbiased computational design of mutants or chemically modified proteins with wanted optical properties.

          Related collections

          Author and article information

          Journal
          Proc. Natl. Acad. Sci. U.S.A.
          Proceedings of the National Academy of Sciences of the United States of America
          Proceedings of the National Academy of Sciences
          0027-8424
          0027-8424
          Nov 14 2006
          : 103
          : 46
          Affiliations
          [1 ] Dipartimento di Chimica, Università di Siena, via Aldo Moro 2, I-53100 Siena, Italy.
          Article
          0604048103
          10.1073/pnas.0604048103
          1859901
          17090682
          f1cb9092-75d9-49ee-9cf6-8c4bb4c66320
          History

          Comments

          Comment on this article