Regulated Incorporation of Two Different Metal Ions into Programmed Sites in a Duplex by DNA Polymerase Catalyzed Primer Extension†
This work was supported in part by a Grant-in-Aid for Scientific Research (C) (24550199) (for H.U.) and Scientific Research (A) (24245037) (for A.O.) from the Ministry of Education, Science, Sports and Technology (Japan).
Graphical Abstract
(Quick) silver DNA: HgII and AgI ions were found to specifically trigger DNA polymerase catalyzed primer extension in the absence of a Watson–Crick matched nucleotide through the formation of T–HgII–T and newly discovered C–AgI–T base pairs. The strict base recognition by the metal ions enabled regulated incorporation of the two different metal ions into programmed sites in duplex DNA.
Abstract
Metal-mediated base pairs formed by the coordination of metal ions to natural or artificial bases impart unique chemical and physical properties to nucleic acids and have attracted considerable interest in the field of nanodevices. AgI ions were found to mediate DNA polymerase catalyzed primer extension through the formation of a C–AgI–T base pair, as well as the previously reported C–AgI–A base pair. The comparative susceptibility of dNTPs to AgI-mediated enzymatic incorporation into the site opposite cytosine in the template was shown to be dATP>dTTP≫dCTP. Furthermore, two kinds of metal ions, AgI and HgII, selectively mediate the incorporation of thymidine 5′-triphosphate into sites opposite cytosine and thymine in the template, respectively. In other words, the regulated incorporation of different metal ions into programmed sites in the duplex by DNA polymerase was successfully achieved.
