A Novel Ag I ‐DNA Rod Comprising a One‐Dimensional Array of 11 Silver Ions within a Double Helical Structure

DNA/RNA duplexes containing metal‐ion‐mediated base pairs (metallo‐base pairs) have potential applications in developing nucleic acid‐based nanodevices and genetic code expansion. Many metallo‐base pairs are formed within duplexes stabilized by Watson–Crick base pairs. Recently, the crystal structure of an Ag I ‐DNA nanowire with an uninterrupted one‐dimensional silver array was determined. Here, we present a new DNA helical wire, the “Ag I ‐DNA rod”, containing an uninterrupted array of 11 Ag I ions. The Ag I ‐DNA rod consisted of only C‐Ag I ‐C, G‐Ag I ‐G, G‐Ag I ‐5‐bromouracil ( Br U), and Br U‐Ag I ‐ Br U metallo base pairs, with no Watson–Crick pairs. The Ag I ‐DNA rods were connected by non‐canonical G–G pairs in crystals. Notably, data from our absorbance, circular dichroism, nuclear magnetic resonance, and mass spectrometry analyses suggested that the Ag I ‐DNA rods formed in solution, as well as within crystals.