Intermolecular Coulombic Decay in Biology: The Initial Electron Detachment from FADH^– in DNA Photolyases

Abstract

Intermolecular coulombic decay (ICD) is an efficient mechanism of low-energy electron generation in condensed phases and is discussed as their potential source in living cells, tissues, and materials. The first example of ICD as an operating mechanism in real biological systems, that is, in the DNA repair enzymes photolyases, is presented. Photolyase function involves light-induced electron detachment from a reduced flavin adenine dinucleotide (FADH(-)), followed by its transfer to the DNA-lesion triggering repair of covalently bound nucleobase dimers. Modern quantum chemical methods are employed to demonstrate that the transferred electron is efficiently generated via a resonant ICD process between the antenna pigment and the FADH(-) cofactors.

Photolyase: Dynamics and electron-transfer mechanisms of DNA repair

“…Due to the unfavorable driving forces (ΔG 0 ~0–+0.1 eV) of the forward ET reactions [79, 80], we have a back ET (BET) process directly to the initial excited state (BET1a) in addition to the BET process to the original ground state (BET1b). In some PLs, we also observed a very small fraction of long-lived LfH • due to the autoionization process of LfH − * that has been recently proposed by theory [84]. Together with the transients obtained from the visible range that detect both LfH − * and LfH • , we globally analyzed these dynamics and derived the average forward ET (FET1) times of 1450, 1340, 1800, 1590, 564 and 2980 ps, the average BET1a times of 730, 1230, 800, 1029, 1505 and 690 ps, and the average BET1b times of 28, 26, 20, 715, 17 and 22 ps for EcPL, AnPL, AtCRY3, DmPL, AtPL and CcPL, respectively, with a nearly constant deactivation lifetime of 6 ns.…”

Relativistic decay widths of autoionization processes: The relativistic FanoADC-Stieltjes method

“…These excited systems can decay via multiple pathways like photon emission, coupling to vibrational degrees of freedom or via electronic decay processes like the Auger decay, 1,2 or the manifold of Interatomic/Intermolecular Coulombic Decay (ICD) processes, 3,4 both being autoionization processes. The latter can occur in small [5][6][7] and large 4,[8][9][10][11] noble gas clusters, as well as clusters of molecules like water, [12][13][14][15][16] ammonia, 17 or hydrogen fluoride 3,18 after exposure to synchrotron radiation, in enzymes of the human body, 19 in the mechanisms of cancer drugs, [20][21][22][23][24][25] and quantum dots in semiconductors 26 just to name a few examples.…”

Strong field control of the interatomic Coulombic decay process in quantum dots

“…[1] -this slogan summarizes the nearly twenty years of success history of the ultrafast interatomic (intermolecular) Coulombic decay (ICD) process from its first theoretical prediction by Cederbaum, Zobeley, and Tarantelli [2] to its widespread theoretical and experimental observation [3,4] in various atomic and molecular systems including clusters of noble gas atoms [5,6,7,8], endohedral fullerenes [9,10,11], aqueous solutions [12,13,14,15,16,17], biological systems [18,19,20,21,22,23], and nanomaterials [24,25,26] just to name a few.…”