Flavoproteins, containing flavin chromophores, are enzymes capable of transferring electrons at very high speeds. The ultrafast photoinduced electron-transfer (ET) kinetics of riboflavin binding protein to the excited riboflavin was studied by femtosecond spectroscopy and found to occur within a few hundred femtoseconds [Zhong and Zewail, Proc. Natl. Acad. Sci. U.S.A.2001, 98, 11867–11872]. This ultrafast kinetics was attributed to the presence of two aromatic rings that could transfer the electron to riboflavin: the side chains of tryptophan 156 and tyrosine 75. However, the underlying ET mechanism remained unclear. Here, using a hybrid quantum mechanical–molecular dynamics approach, we perform ET dynamics simulations taking into account the motion of the protein and the solvent upon ET. This approach reveals that ET occurs via a major reaction channel involving tyrosine 75 (83%) and a minor one involving tryptophan 156 (17%). We also show that the protein environment is designed to ensure the fast quenching of the riboflavin excited state.
Zanetti-Polzi, L., Aschi, M., Amadei, A., & Daidone, I. (2017). Alternative Electron- Transfer Channels Ensure Ultrafast Deactivation of Light-Induced Ex- cited States in Riboflavin Binding Protein. THE JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 8(14), 3321-3327.
Tipologia: | Articolo su rivista |
Citazione: | Zanetti-Polzi, L., Aschi, M., Amadei, A., & Daidone, I. (2017). Alternative Electron- Transfer Channels Ensure Ultrafast Deactivation of Light-Induced Ex- cited States in Riboflavin Binding Protein. THE JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 8(14), 3321-3327. |
IF: | Con Impact Factor ISI |
Lingua: | English |
Settore Scientifico Disciplinare: | Settore CHIM/02 - Chimica Fisica |
Revisione (peer review): | Esperti anonimi |
Tipo: | Articolo |
Rilevanza: | Rilevanza internazionale |
Digital Object Identifier (DOI): | http://dx.doi.org/10.1021/acs.jpclett.7b01575 |
Stato di pubblicazione: | Pubblicato |
Data di pubblicazione: | 2017 |
Titolo: | Alternative Electron- Transfer Channels Ensure Ultrafast Deactivation of Light-Induced Ex- cited States in Riboflavin Binding Protein |
Autori: | |
Autori: | Zanetti-Polzi, L; Aschi, M; Amadei, A; Daidone, I |
Appare nelle tipologie: | 01 - Articolo su rivista |