Energy bands in DNA

Abstract

In the first part of this review paper on energy band calculations of different periodic DNA models the generalization of the different LCAO schemes to solids with arbitrary number of orbitals within the elementary cell is outlined. The tight binding approximation and the semi-empirical SCF LCAO (Pariser-Parr-Pople) crystal orbital approximations which have been applied for the calculations, are described in somewhat more detail. Further the possibility of ab initio calculations on periodic DNA models is discussed.According to the obtained results in the cases of homopolynucleotides and of the poly(A-T) and poly(G-C) systems the energy bands are fairly broad, while in the cases of more complicated periodic DNA models they are rather narrow. Finally the small effect of water and the very strong effect of Mg2+ ion impurities, respectively, on the band structure of poly (G-C) are discussed.

Real Space Theory for Electron and Phonon Transport in Aperiodic Lattices via Renormalization

“…Self-assembled deoxyribonucleic acid (DNA) molecular wires, built by cytosine-guanine (CG) or adenine-thymine (AT) stacked pairs attached to the double-helix structure through sugar-phosphate backbones, may behave as a low-dimensional conductor, semiconductors, or insulators, depending on the system length and base-pair sequences [126,127]. Ab-initio [128,129] and semi-empirical [130,131] studies of DNA molecules were carried out and, among them, the latter has the advantage of being simple and suitable for the analysis of electronic transport in aperiodic double chains with macroscopic length. The DNA molecules can be modelled as a double-strand ladder of coarse grains, which has been transformed into a single string of base pairs with dangling backbones, known as the fishbone model, and in turn, it was reduced to a single chain after a two-step renormalization at each base pair [132].…”

Quantum molecular biological investigation of the onset of cancer

“…All these events can seriously disturb the cell's selfregulation mechanism or the programming cell death and the cells could turn into a new stationary state, which could be considered precancerous. [3,58] If many oncogenes become freely readable the tumor could grow much faster. Conversely, if in a nucleosome the protein shield of DNA gets injured the procedure described before takes place probably more quickly.…”

Perturbation of cell-selfregulation through oncoproteins

“…In order to build the mathematical models one has to collect the most important data on matter, energy, and information transport within a cell and between cells. For the understanding of the regulation within a cell one should use the results of quantum mechanical investigations of energy and charge transport [13] in biopolymers and the results obtained from the interactions between biopolymers [ 141.…”

“…In a previous article [7] we have reviewed the most probable local as well as longrange effects caused by carcinogen binding to DNA andtor proteins. In a subsequent publication [8] the role of conformational solitons caused by the release of bulky carcinogens bound to a nucleotide base stack (the carcinogen binding distorts the conformation of the double helix and therefore also changes the interaction between the electrons belonging to the stacked bases) is discussed in detail as one of the most probable forms of the long-range effects of carcinogns via which they can influence DNA-protein interactions in a nucleoprotein.…”