Charge Transport in DNA with a Base Pair Opening

We investigate the effect of a base pair opening on the charge transport in double-stranded DNA. Poly(G)-poly(C) homopolymer, with a donor and an acceptor located on the same strand (say, strand 1), is studied specifically. When the incident charge energy lies within the molecular band of strand 1, the charge transport is unaffected by the base pair opening, irrespective of the number of opened base pairs and their sites. In contrast, when the incident energy lies inside the band of the complementary strand (strand 2), the charge transport decreases drastically when a base pair opening occurs at the site nearest to a donor or an acceptor.