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arXiv · 1304.8009

Dynamics of ion-phosphate lattice of DNA in left-handed double helix form

S. M. Perepelytsya·S. N. Volkov
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Abstract

The conformational vibrations of Z-DNA with counterions are studied in framework of phenomenological model developed. The structure of left-handed double helix with counterions neutralizing the negatively charged phosphate groups of DNA is considered as the ion-phosphate lattice. The frequencies and Raman intensities for the modes of Z-DNA with Na+ and Mg2+ ions are calculated, and the low-frequency Raman spectra are built. At the spectra range about the frequency 150 cm-1 new mode of ion-phosphate vibrations is found, which characterizes the vibrations of Mg2+ counterions. The results of our calculations show that the intensities of Z-DNA modes are sensitive to the concentration of magnesium counterions. The obtained results describe well the experimental Raman spectra of Z-DNA.

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S. M. Perepelytsya, S. N. Volkov. 2013-04-30. Dynamics of ion-phosphate lattice of DNA in left-handed double helix form. https://arxiv.org/abs/1304.8009

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