Study of ethidium bromide interaction peculiarities with DNA.
The helix-coil transition of DNA-ethidium bromide complexes in an interval of ionic strength of 2.0 x 10(-3) M < or = muNa+ < or = 2.0 x 10(-2) M has been investigated. It has been revealed that at the certain high ligand-DNA ratios (r(b)) the transition interval of the complex--(deltaT) becomes equal to that of DNA itself (deltaTo). It has been shown that the values of r(b) at which delta deltaT=deltaT-deltaT0=0 depends on ionic strength of a solution. Further increasing of ligand concentration leads to its conversion from stabilizer into the destabilizer of the double-stranded DNA.
Vardevanyan
P O
PO
Biophysics Department of the Biological Faculty of Yerevan State University, Armenia. kensafiz@ysu.am
Antonyan
A P
AP
Manukyan
G A
GA
Karapetyan
A T
AT
D000818:Animals; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D004996:Ethidium / Q000737:chemistry*; D006358:Hot Temperature; D008024:Ligands; D009690:Nucleic Acid Conformation; D009994:Osmolar Concentration; D012996:Solutions
D008024:Ligands; D012996:Solutions; D004247:DNA; D004996:Ethidium