Dimethylsulfoxide-stabilized conformer of guanine-adenine repeat strand of DNA.
Circular dichroism spectroscopy and other methods are used to show that the addition of dimethylsulfoxide causes reversible folding of the (GA)(10) strand of DNA into an ordered single-stranded conformer. The ordered conformer melts in a cooperative way and it does not contain protonated adenine. The (TA)(10), (A)(20), and (G)(20) are all unstable in this conformer. To the best of our knowledge, this is the first known ordered conformer of DNA that is stabilized by dimethylsulfoxide. This conformer might be a DNA analog of the protein alpha helix, which is an interesting idea for thinking about the evolution of DNA.
Kypr
J
J
Institute of Biophysics of the Academy of Sciences of the Czech Republic, Královopolská 135, CZ-612 65 Brno, Czech Republic. mifi@ibp.cz
Vorlícková
M
M
D000225:Adenine; D002942:Circular Dichroism; D004277:DNA, Single-Stranded / Q000737:chemistry*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology*; D004355:Drug Stability; D006147:Guanine; D009690:Nucleic Acid Conformation / Q000187:drug effects*; D012091:Repetitive Sequences, Nucleic Acid
D004277:DNA, Single-Stranded; D006147:Guanine; D000225:Adenine; D004121:Dimethyl Sulfoxide