Structural and physicochemical features on the metal-mediated base pairs.
The chemical structure of the mercury-mediated T-T pair (T-Hg(I)I-T) was determined with (15)N NMR spectroscopy. In order to determine the chemical structure of the T-Hg(I)I-T pair, (15)N-(15)N J-coupling across a metal center (2JNN) was employed. Notably, this is the first observation of (2)J(NN) in a biological macromolecule (DNA duplex). This pairing mode was found to be a irregular metal ion-binding mode for DNA and RNA molecules, in which imino proton-metal exchange processes are included. Accordingly, (2)J(NN) is highly important for the determination of the chemical structures of metal-mediated base pairs.
Tanaka
Yoshiyuki
Y
Graduate School of Pharmaceutical Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai 980-8578, Japan. tanaka@mail.pharm.tohoku.ac.jp
Oda
Shuji
S
Yamaguchi
Hiroshi
H
Haruta
Kaichiro
K
Kawamura
Takuya
T
Kondo
Yoshinori
Y
Uchiyama
Tomomi
T
Takashi
Miura
M
Takeuchi
Hideo
H
Torigoe
Hidetaka
H
Kojima
Chojiro
C
Ono
Akira
A
D020029:Base Pairing; D004247:DNA / Q000737:chemistry; D008628:Mercury / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular; D013941:Thymine / Q000737:chemistry*
D004247:DNA; D008628:Mercury; D013941:Thymine