Phase Behavior of Single DNA in Mixed Solvents
| Autor: | Sergey M. Mel'nikov, Björn Lindman, Malek O. Khan, Bo Jönsson |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Physics::Biological Physics
Quantitative Biology::Biomolecules Phase transition Aqueous solution Ethylene General Chemistry Dielectric Biochemistry Catalysis Condensed Matter::Soft Condensed Matter Solvent chemistry.chemical_compound Colloid and Surface Chemistry chemistry Phase (matter) Acetone Organic chemistry Physical chemistry Physics::Chemical Physics Ethylene glycol |
| Zdroj: | Journal of the American Chemical Society. 121:1130-1136 |
| ISSN: | 1520-5126 0002-7863 |
| DOI: | 10.1021/ja981491e |
| Popis: | Compaction of single large dsDNA chains in aqueous solution in the presence of primary alcohols, acetone, and ethylene glycol has been studied experimentally with the use of a fluorescence microscopy technique. It is found that in the presence of all studied organic solvents single DNA molecules exhibit a discrete phase transition from an elongated coiled to a compacted globular conformation. Interestingly, DNA phase transition occurred at various weight fractions of organic solvents in aqueous solution, but at similar dielectric constants of mixed solvent for all studied primary alcohols and acetone. On the other hand, the dielectric constant of ethylene glycol−water mixtures corresponding to the collapsing transition in single DNA differed from that for the other studied systems. The explanation of this phenomenon comes through consideration of the existence of ethylene glycol conformers with various polarities in aqueous solution. Thus, the dielectric permittivity of the solvent is a key factor that de... |
| Databáze: | OpenAIRE |
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