Influence of temperature and base-pair twisting motion frequency on electron transport of guanine-quadruplex DNA molecule

Abstract

Electron transport of Guanin-quadruplex DNA (G4-DNA) molecule has been studied by considering temperature and twisting motion frequency. The calculation is done for 32 base pairs long G4 DNA molecules. G4-DNA molecule is a collection of G-quartet, a square structure consists of four G (guanine) base with a G base is located at each corner of the square, stacked on top each other. G4-DNA molecules are modeled using tight binding Hamiltonian. The calculation of transport electron in the form of transmission probability is carried out by employing transfer matrix technique in concert with scattering matrix method. Landauer-Büttiker formalism is called in service when computing the I-V characteristics of the molecule from transmission probability. The twisting angle of base pairs is correlated to interbase electron hopping constant within Slater-Koster-Harrison semi-empirical theory. The calculation is done for several twisting motion frequencies and temperatures. The result shows that electron transport on G4-DNA depends on twisting motion frequency of bases, such that as the frequency increases, the current and transmission probability also increases. On the contrary, the current and transmission probability decreases as temperature increases.