Alexander V. Nemukhin

TL;DR: The focus of this review is on the most recent experimental and theoretical work on photoinduced transformations in fluorescent proteins, highlighting the interplay between photochemistry and other channels (fluorescence, radiationless relaxation, and intersystem crossing).

TL;DR: It is demonstrated that a three-center Hückel-like model provides a useful framework for understanding properties of FPs, and can explain changes in absorption wavelength upon protonation or other structural modifications of the chromophore, the magnitude of transition dipole moment, barriers to isomerization, and even non-Condon effects in one- and two-photon absorption.

TL;DR: Molecular models for the dark and light states of the BLUF domain of the Rhodobacter sphaeroides AppA protein are developed based on the crystal structures and quantum-mechanical simulations and light-induced isomerization of an amino acid residue instead of a chromophore represents a feature that has not been described previously in photoreceptors.

TL;DR: Estimations of the vertical excitation energy obtained with the equation-of-motion coupled cluster with the singles and doubles method, a multireference perturbation theory corrected approach MRMP2 as well as the time-dependent density functional theory with range-separated functionals reveal a continuum of "ionized" states, which embeds the bright ππ* transition.

TL;DR: The results reproduce essential features of previous ab initio calculations of the anionic form of the chromophore and provide an extension for the neutral, cationic, and zwitterionic forms, which are important in the protein environment.