Relative Strand Orientation in a DNA Duplex Controls the Nuclearity of a Metal-Mediated Base Pair

Mandal S, Hebenbrock M, Müller J

Zusammenfassung

1,N6-Ethenoadenine (εA) and cytosine (C) are able to form two different metal-mediated base pairs. When the glycosidic bonds are arranged in a cisoid manner (i.e., in antiparallel-stranded DNA), the εA:C mispair binds one AgI ion, leading to a mononuclear εA-AgI-C base pair that contains a synergistic hydrogen bond. In contrast, a transoid orientation of the glycosidic bonds (as found in parallel-stranded DNA) results in the formation of a dinuclear metal-mediated base pair εA-AgI2-C.