Hole mobilities of periodic models of DNA double helices in the nucleosomes at different temperatures

Chemical Physics Letters (Impact Factor: 1.9). 03/2013; 565:128-131. DOI: 10.1016/j.cplett.2013.02.021


Using the Hartree-Fock crystal orbital method band structures of poly(G-C) and poly(A-T) were calculated (G, etc. means a nucleotide) including water molecules and Na+ ions. Due to the close packing of DNA in the ribosomes the motion of the double helix and the water molecules around it are strongly restricted, therefore the band picture can be used. The mobilities were calculated from the highest filled bands. The hole mobilities increase with decreasing temperatures. They are of the same order of magnitude as those of poly(A) and poly(T). For poly(G) the result is ∼5 times larger than in the poly(G-C) case.

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Available from: Attila Bende, Sep 05, 2014
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    ABSTRACT: Accurate stereostructure of DNA in the nucleosomes has been established recently with the aid of more precise crystal structure investigations. Using this structure, Hartree–Fock crystal orbital calculations have been performed on the DNA parts of the nucleosomes. The obtained band structure was used to calculate the hole mobilities of the corresponding DNA parts. These results were used further to investigate the effect of Cl− ions which enter in the cell nucleus through channels in the nuclear membrane. Our results show how Cl− ions can weaken the DNA–protein interactions which can lead to the onset of cancer. Other molecules can also bind to DNA or photon can excite a nucleotide base in the stack. In both cases, a soliton can appear which causes long-range effect (disturbance of protein synthesis, double strand breaking). © 2014 Wiley Periodicals, Inc.
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