Biochemical and Biophysical Research Communications, Vol.495, No.4, 2559-2565, 2018
Studying compaction-decompaction of DNA molecules induced by surfactants
The mechanism and detailed processes of DNA compaction and decompaction are essential for the life activities, as well as for the researches in the molecular biology, genetics and biomedicine. The compaction of two kinds of DNA molecules caused by Cetyltrimethyl Ammonium Bromide (CTAB) and their decompaction induced with sodium dodecyl sulfate (SDS) or excessive amount of CTAB have been investigated with multiple perspectives such as the UV-VIS spectrophotometry, dynamic light scattering, and zeta potential. The compaction phenomenon of DNA can easily be observed when the CTAB combines with the DNA, not just when the molar ratio Q(CTAB)/Q(DNA) is approximately equal to 1 as the conventional recognition, but also when Q(CTAB)/Q(DNA) <1,DNA can be compacted; Molecular state of DNA is only changed in the conformational structure, but not in the chemical structure. Finally, a model is suggested to help catch on the biophysical mechanism of DNA chain conformational change. (C) 2018 Elsevier Inc. All rights reserved.