Silver turns up the A-C: In the presence of Ag(I) ions, a DNA polymerase incorporated deoxyadenosine (from dATP) at the site opposite cytosine in the template strand to afford the full-length product (see scheme), meaning that DNA polymerases prefer a C-Ag(I)-A base pair to the more thermodynamically stable C-Ag(I)-C base pair.

Mit Silber zu A–C: In Gegenwart von AgI‐Ionen baut eine DNA‐Polymerase Desoxyadenosin (aus dATP) gegenüber einem Cytosinrest im Templatstrang unter Bildung des Volllängenprodukts ein (siehe Schema). Das bedeutet, dass DNA‐Polymerasen ein C‐AgI‐A‐Basenpaar dem thermodynamisch stabileren C‐AgI‐C‐Basenpaar vorziehen.

Spectroscopic characterization of AgI‐ion‐mediated C‐AgI‐A and C‐AgI‐T base pairs found in primer extension reactions catalyzed by DNA polymerases was conducted. UV melting experiments revealed that C‐A and C‐T mismatched base pairs in oligodeoxynucleotide duplexes are specifically stabilized by AgI ions in 1:1 stoichiometry in the same manner as a C‐C mismatched base pair. Although the stability of the mismatched base pairs in the absence of AgI ions is in the order C‐A≈C‐T>C‐C, the stabilizing effect of AgI ions follows the order C‐C>C‐A≈C‐T. However, the comparative susceptibility of dNTPs to AgI‐mediated enzymatic incorporation into the site opposite templating C is dATP>dTTP≫dCTP, as reported. The net charge, as well as the size and/or shape complementarity of the metal‐mediated base pairs, or the stabilities of mismatched base pairs in the absence of metal ions, would be more important than the stability of the metallo‐base pairs in the replicating reaction catalyzed by DNA polymerases.

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