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arXiv · 1107.4215

T4 DNA condensation in water-alcohol media

M. O. Gallyamov·O. A. Pyshkina·V. G. Sergeyev·I. V. Yaminsky
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Abstract

The process of compaction of high molecular weight DNA T4 is investigated directly in a AFM liquid cell. The AFM-images of globules formed by DNA molecules in the result of compaction in water-alcohol environments at high izopropanol concentration (80%) are received; it is found that at intermediate concentration of izopropanol (40-50%) the DNA molecules form partially compacted formations in which the separate coils of macromolecules twist in toroidal structures. It is shown using the technique of deconvolution of the AFM-images that the globule include only one closely packed DNA molecule. The model of DNA packing is proposed on the basis of AFM experiment.

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M. O. Gallyamov, O. A. Pyshkina, V. G. Sergeyev, I. V. Yaminsky. 2011-07-21. T4 DNA condensation in water-alcohol media. https://arxiv.org/abs/1107.4215

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