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Continuity of states between the cholesteric → line hexatic transition and the condensation transition in DNA solutions.

ABSTRACT: A new method of finely temperature-tuning osmotic pressure allows one to identify the cholesteric → line hexatic transition of oriented or unoriented long-fragment DNA bundles in monovalent salt solutions as first order, with a small but finite volume discontinuity. This transition is similar to the osmotic pressure-induced expanded → condensed DNA transition in polyvalent salt solutions at small enough polyvalent salt concentrations. Therefore there exists a continuity of states between the two. This finding, together with the corresponding empirical equation of state, effectively relates the phase diagram of DNA solutions for monovalent salts to that for polyvalent salts and sheds some light on the complicated interactions between DNA molecules at high densities.

SUBMITTER: Yasar S

PROVIDER: S-EPMC4220286 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature

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Continuity of states between the cholesteric → line hexatic transition and the condensation transition in DNA solutions.

Yasar Selcuk S Podgornik Rudolf R Valle-Orero Jessica J Johnson Mark R MR Parsegian V Adrian VA

Scientific reports 20141105

A new method of finely temperature-tuning osmotic pressure allows one to identify the cholesteric → line hexatic transition of oriented or unoriented long-fragment DNA bundles in monovalent salt solutions as first order, with a small but finite volume discontinuity. This transition is similar to the osmotic pressure-induced expanded → condensed DNA transition in polyvalent salt solutions at small enough polyvalent salt concentrations. Therefore there exists a continuity of states between the two ...[more]

PMID: 25371012

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