title: A highly stabilizing silver(I)-mediated base pair in parallel-stranded DNA.
abstract: The first parallel-stranded DNA duplex with Hoogsteen base pairing that readily incorporates an Ag(+) ion into an internal mispair to form a metal-mediated base pair has been created. Towards this end, the highly stabilizing 6 FP-Ag(+)-6 FP base pair comprising the artificial nucleobase 6-furylpurine (6 FP) was devised. A combination of temperature-dependent UV spectroscopy, CD spectroscopy, and DFT calculations was used to confirm the formation of this base pair. The nucleobase 6 FP is capable of forming metal-mediated base pairs both by the Watson-Crick edge (i.e. in regular antiparallel-stranded DNA) and by the Hoogsteen edge (i.e. in parallel-stranded DNA), depending on the oligonucleotide sequence and the experimental conditions. The 6 FP-Ag(+)-6 FP base pair within parallel-stranded DNA is the most strongly stabilizing Ag(+)-mediated base pair reported to date for any type of nucleic acid, with an increase in melting temperature of almost 15 °C upon the binding of one Ag(+) ion.
authors: Westfälische Wilhelms-Universität Münster, Institut für Anorganische und Analytische Chemie & NRW Graduate School of Chemistry, Corrensstrasse 28/30, 48149 Münster (Germany).
authors: Indranil
authors: I
authors: Sinha
authors: Célia
authors: C
authors: Fonseca Guerra
authors: Jens
authors: J
authors: Müller
mesh_terms: D020029:Base Pairing; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D044367:Phase Transition; D011687:Purines / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D044366:Transition Temperature
chemical_list: D011687:Purines; D012834:Silver; D004247:DNA
keywords: bioinorganic chemistry; metal-mediated base pair; parallel-stranded DNA; purines; silver