Base sequence dependence of charge transport via short DNA bridges

Abstract

Charge transfer in a donor -short bridge -acceptor system is studied within a simple model of a DNA molecule. A difference in transfer rates via two bridges containing similar bases though with opposite sequences is demonstrated. The result calls for experimental verification.

The influence of the water surrounding on a long‐distance electron transport in the DNA

“…In the description of incoherent transport phenomena it is usually presumed that the charge carrier is at each instant completely localized on one of the localization centers [11]. Our previous calculations [10]…”

“…For such a potential we straightforwardly solve the one-dimensional time-dependent Schrödinger equation which allows one to study the time evolution of the wave function Ψ(x,t). A similar model was previously used to examine the sequence dependence of DNA transport via short bridges as well as the dependence of the charge transport on the homogenous bridge length in the presence of the dynamic disorder [10]. The overlap of the eigenfunctions of the isolated wells simulates the π-overlap between the adjacent bases of the real DNA chain.…”

“…Due to interactions with the surrounding water molecules, the geometry of the DNA double helix (distances and angles between the bases) can change in time. In our one-dimensional model this process is simulated by the dynamic disorder [12,10]. The distortion ∆x i (t) from the equilibrium position x i of any potential well can vary in time and the potential becomes time-dependent, i.e.…”

“…Our interest is focused on the long-distance charge transfer between guanine (G) bases. If the bridge between the bases consists of less than 5 bases the most effective mechanism of charge transport is hopping between G bases [3,10]. We used for calculations a particular sequence CGCGATCGCG with a G + donor attached at the 3' end and a GGG acceptor (trap) at the 5' end of the DNA molecule.…”

DNA Conduction: The Issue of Static Disorder, Dynamic Fluctuations and Environmental Effects

“…Matulewski et al [140,141] have investigated the effect of dynamic disorder on the charge transfer between donor and acceptor centers in a model DNA molecule. They calculated the charge transfer rates between two g-bases separated by an AT-bridge.…”