Effects of dynamic disorder on the charge transport via DNA molecules

Abstract

Electron hopping transport along the DNA chain is studied theoretically by a straightforward numerical solution of the time-dependent Schrödinger equation. Results are given for the hole transition rates between two guanine bases bridged by sequences of the adenine-thymine bases with various lengths. Two models are considered: (i) with time-independent chain structure and (ii) with positions of bases on the bridge oscillating with time. It is shown that only the latter model is consistent with experimental data. The problem of the incoherence in the hopping transport mechanism is discussed.

Dynamics of Electron Transport by Elastic Bending of Short DNA Duplexes. Experimental Study and Quantitative Modeling of the Cyclic Voltammetric Behavior of 3‘-Ferrocenyl DNA End-Grafted on Gold

“…Electrochemical characterization of molecular layers of end-grafted redox-labeled dsDNA has, on the opposite, been intensively used to examine the electron transport properties of dsDNA, − but most of these works neglected DNA chain motion as a possible charge transport mechanism. However, the relevance of DNA flexibility to electron transport along duplex DNA is now increasingly recognized since recent theoretical calculations, and real-time spectroscopic results, tend to show that electron propagation, over distances longer than a few base pairs, necessarily requires coupling of base-to-base electron hopping with conformational rearrangement of the bases, induced by the elastic deformation of the strand 10d. The intertwinement of these two components of electron transport makes extremely difficult the full quantitative modeling of electron propagation along duplex DNA.…”

Static and dynamic aspects of DNA charge transfer: a theoretical perspective

“…Its foundation is well rooted in chemical kinetics, and although some of its minor technical details and parameters have been disputed, it has never been seriously challenged or even falsified. An interesting alternative has, however, been suggested by Matulewski and coworkers: 40 Here, dynamic disorder considered within a highly simplified one-electron barrier model induces a plateau in the transfer rate as a function of the guanine-guanine distance. We will return to the detailed role of dynamic aspects in the third section of the paper.…”

Quantum diffusion in polaron model of poly(dG)-poly(dC) and poly(dA)-poly(dT) DNA polymers

“…For the present, a number of the polaron models have been proposed to describe charge transfer/transport in DNA polymers, see, for example, [9,14,15,16,17,18]. On the other hand, computer simulations have pinpointed the crucial significance of dynamical disorder for DNA transfer/transport [20,21,22,23,24], and several attempts to formulate stochastical models for the interplay of the former and the latter have already appeared in the literature, see, for example, [25,26].…”