Flexibility of short ds-DNA intercalated by a dipyridophenazine ligand
نویسندگان
چکیده
We use Förster Resonant Energy Transfer (FRET) in order to measure the increase of flexibility of short ds-DNA induced by the intercalation of dipyridophenazine (dppz) ligand in between DNA base pairs. By using a DNA double strand fluorescently labeled at its extremities, it is shown that the end-to-end length increase of DNA due to the intercalation of one dppz ligand is smaller than the DNA base pair interdistance. This may be explained either by a local bending of the DNA or by an increase of its flexibility. The persistence length of the formed DNA/ligand is evaluated. The described structure may have implications in the photophysical damages induced by the complexation of DNA by organometallic molecules.
منابع مشابه
Study of picosecond processes of an intercalated dipyridophenazine Cr(III) complex bound to defined sequence DNAs using transient absorption and time-resolved infrared methods.
Picosecond transient absorption (TA) and time-resolved infrared (TRIR) measurements of rac-[Cr(phen)2(dppz)](3+) () intercalated into double-stranded guanine-containing DNA reveal that the excited state is very rapidly quenched. As no evidence was found for the transient electron transfer products, it is proposed that the back electron transfer reaction must be even faster (<3 ps).
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