title: Highly Stable Double-Stranded DNA Containing Sequential Silver(I)-Mediated 7-Deazaadenine/Thymine Watson-Crick Base Pairs.
abstract: The oligonucleotide d(TX)9 , which consists of an octadecamer sequence with alternating non-canonical 7-deazaadenine (X) and canonical thymine (T) as the nucleobases, was synthesized and shown to hybridize into double-stranded DNA through the formation of hydrogen-bonded Watson-Crick base pairs. dsDNA with metal-mediated base pairs was then obtained by selectively replacing W-C hydrogen bonds by coordination bonds to central silver(I) ions. The oligonucleotide I adopts a duplex structure in the absence of Ag(+) ions, and its stability is significantly enhanced in the presence of Ag(+) ions while its double-helix structure is retained. Temperature-dependent UV spectroscopy, circular dichroism spectroscopy, and ESI mass spectrometry were used to confirm the selective formation of the silver(I)-mediated base pairs. This strategy could become useful for preparing stable metallo-DNA-based nanostructures.
authors.affiliation: Facultad de Ciencias, Departamento Química Inorgánica, Universidad de Granada, Avd. Fuentenueva s/n, 18071, Granada, Spain.
authors.forename: Noelia
authors.initials: N
authors.lastname: Santamaría-Díaz
authors.affiliation: Facultad de Ciencias, Departamento Química Inorgánica, Universidad de Granada, Avd. Fuentenueva s/n, 18071, Granada, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Méndez-Arriaga
authors.affiliation: Facultad de Ciencias, Departamento Química Inorgánica, Universidad de Granada, Avd. Fuentenueva s/n, 18071, Granada, Spain.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Salas
authors.affiliation: Facultad de Ciencias, Departamento Química Inorgánica, Universidad de Granada, Avd. Fuentenueva s/n, 18071, Granada, Spain. magalindo@ugr.es.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Galindo
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D020029:Base Pairing; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D006860:Hydrogen Bonding; D009690:Nucleic Acid Conformation; D012834:Silver / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D013941:Thymine / Q000737:chemistry* / Q000378:metabolism
chemical_list: C043837:7-deazaadenine; D012834:Silver; D004247:DNA; D000225:Adenine; D013941:Thymine
keywords: DNA; Watson-Crick base pairing; bioinorganic chemistry; hydrogen bonds; silver