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Updated: Jul 4, 2026

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Origin of the absorption maxima of the photoactive yellow protein resolved via ab initio multiconfigurational methods
Abstract:
We discuss the role of the protein in controlling the absorption spectra of photoactive yellow protein (PYP), the archetype xanthopsin photoreceptor, using quantum mechanics/molecular mechanics (QM/MM) methods based on ab initio multireference perturbation theory, combined with molecular dynamics (MD) simulations. It is shown that in order to get results in agreement with the experimental data, it is necessary to use a model that allows for a proper relaxation of the whole system and treats the states involved in the electronic spectrum in a balanced way, avoiding biased results due to the effect of nonrepresentative electrostatic interactions on the chromophore.
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