title: Metal ion binding of modified pyrimidine-base pairs in DNA duplexes.
abstract: We report the synthesis and metal ion-binding properties of DNA duplexes containing 5-substituted uracil ((X)U) pairs, such as 5-bromouracil, 5-fluorouracil and 5-cyanouracil pairs. Thermal denaturation studies of these modified DNA duplexes revealed that the DNA duplexes were stabilized in the presence of Hg(II) ions in acidic and neutral solutions. On the other hand, the duplexes were stabilized in the presence of Hg(II) and Ag(I) ions. These results indicated that (X)U-Hg(II)-(X)U complex was formed in the acidic and neutral solutions, then, in the basic solutions (X)U-Ag(I)-(X)U complex as well as the (X)U-Hg(II)-(X)U complex were formed. ESI-TOF MS analysis also indicated formation of the metal ion-DNA complexes.
authors.affiliation: Department of Material & Life Chemistry, Faculty of Engineering, Kanagawa University, Yokohama 221-8686, Japan. akiraono@kanagawa-u.ac.jp
authors.forename: Akira
authors.initials: A
authors.lastname: Ono
authors.forename: Kenji
authors.initials: K
authors.lastname: Iwamoto
authors.forename: Kumiko
authors.initials: K
authors.lastname: Sugiyama
authors.forename: Itaru
authors.initials: I
authors.lastname: Okamoto
mesh_terms: D020029:Base Pairing; D004247:DNA / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D008628:Mercury / Q000737:chemistry*; D009691:Nucleic Acid Denaturation; D012834:Silver / Q000737:chemistry*; D014498:Uracil / Q000031:analogs & derivatives*
chemical_list: D007477:Ions; D012834:Silver; D014498:Uracil; D004247:DNA; D008628:Mercury