Reentrant conformational transitions in DNA molecules complexed with cationic surfactant

The authors have established the conditions for the dissociation formation of DNA-CTAB complexes in organic solvents of different polarity. Fluorescence microscopy and CD spectroscopy indicate that DNA-CTAB complexes dissociate into their initial components at intermediate concentrations of alcohol, while conserving the double-stranded structure of native DNA. A further increase in the alcohol concentration leads to restoration of the complex, which is soluble under these conditions, i.e. in low-polarity organic media. As a novel phenomenon on DNA-CTAB interacting system, the authors have found the alcohol-induced reentrant globule-coil-globule transition in T4DNA-CTAB complexes