Optical properties of flavin mononucleotide: A QM/MM study of protein environment effects

We investigate the optical properties of flavin mononucleotide (FMN) as chromophore of a bacterial protein. FMN is studied both in the oxidized and anionic state, by combining hybrid quantum mechanics/molecular mechanics (QM/MM) dynamics with time-dependent density functional theory (TDDFT). Our first-principles calculations show that the inclusion of the protein biological environment is crucial to reproduce the experimental optical spectra. (C) 2011 Elsevier B.V. All rights reserved.