Cationic comb-type copolymers as an artificial nucleic acid-chaperone: spectroscopic analyses for DNA/copolymer interaction.

We have reported previously that the cationic comb-type copolymer, PLL-g-Dex, accelerated DNA strand exchange reaction while stabilizing DNA duplexes. In this research, we showed the effects of cationic PLL-g-Dex copolymer on hybridization of self-complementary octamer oligonucleotides. NMR studies suggested that PLL-g-Dex copolymer preferentially interacted with a duplex DNA rather than a single-stranded DNA, and did not perturb local structures of DNA duplexes. CD studies also supported inert nature of the copolymer upon hybrid structure. From these results we concluded that the accelerating mechanisms of the copolymer did not involved partial perturbation of duplex structure.