TY - JOUR
T1 - Raman spectroscopic detection of the T-HgII-T base pair and the ionic characteristics of mercury
AU - Uchiyama, Tomomi
AU - Miura, Takashi
AU - Takeuchi, Hideo
AU - Dairaku, Takenori
AU - Komuro, Tomoyuki
AU - Kawamura, Takuya
AU - Kondo, Yoshinori
AU - Benda, Ladislav
AU - Sychrovský, Vladimír
AU - Bouř, Petr
AU - Okamoto, Itaru
AU - Ono, Akira
AU - Tanaka, Yoshiyuki
N1 - Funding Information:
Grant-in-Aid for Scientific Research (C) (18550146 and 20550145 to Y.T.) from the Ministry of Education, Culture, Sports, Science and Technology, Japan; Human Frontier Science Program (Young Investigator Grant to Y.T. and V.S.) from the Human Frontier Science Program Organization, France; Grant Agency of the Czech Republic (P205/10/0228 to V.S. and P208/11/0105 to P.B.); Intelligent Cosmos Foundation (to Y.T.); Daiichi-Sankyo Foundation of Life Science (to Y.T. and V.S.). Funding for open access charge: Human Frontier Science Program-Young Investigator Grant.
PY - 2012/7
Y1 - 2012/7
N2 - Developing applications for metal-mediated base pairs (metallo-base-pair) has recently become a high-priority area in nucleic acid research, and physicochemical analyses are important for designing and fine-tuning molecular devices using metallobase- pairs. In this study, we characterized the Hg II-mediated T-T (T-HgII-T) base pair by Raman spectroscopy, which revealed the unique physical and chemical properties of HgII. A characteristic Raman marker band at 1586 cm-1 was observed and assigned to the C4=O4 stretching mode. We confirmed the assignment by the isotopic shift (18O-labeling at O4) and density functional theory (DFT) calculations. The unusually low wavenumber of the C4=O4 stretching suggested that the bond order of the C4=O4 bond reduced from its canonical value. This reduction of the bond order can be explained if the enolate-like structure (N3=C4-O4-) is involved as a resonance contributor in the thymine ring of the T-HgII-T pair. This resonance includes the N-HgII-bonded state (HgII-N3-C4=O4) and the N-Hg II-dissociated state (HgII+ N3=C4-O4-), and the latter contributor reduced the bond order of N-HgII. Consequently, the HgII nucleus in the T-HgII-T pair exhibited a cationic character. Natural bond orbital (NBO) analysis supports the interpretations of the Raman experiments.
AB - Developing applications for metal-mediated base pairs (metallo-base-pair) has recently become a high-priority area in nucleic acid research, and physicochemical analyses are important for designing and fine-tuning molecular devices using metallobase- pairs. In this study, we characterized the Hg II-mediated T-T (T-HgII-T) base pair by Raman spectroscopy, which revealed the unique physical and chemical properties of HgII. A characteristic Raman marker band at 1586 cm-1 was observed and assigned to the C4=O4 stretching mode. We confirmed the assignment by the isotopic shift (18O-labeling at O4) and density functional theory (DFT) calculations. The unusually low wavenumber of the C4=O4 stretching suggested that the bond order of the C4=O4 bond reduced from its canonical value. This reduction of the bond order can be explained if the enolate-like structure (N3=C4-O4-) is involved as a resonance contributor in the thymine ring of the T-HgII-T pair. This resonance includes the N-HgII-bonded state (HgII-N3-C4=O4) and the N-Hg II-dissociated state (HgII+ N3=C4-O4-), and the latter contributor reduced the bond order of N-HgII. Consequently, the HgII nucleus in the T-HgII-T pair exhibited a cationic character. Natural bond orbital (NBO) analysis supports the interpretations of the Raman experiments.
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U2 - 10.1093/nar/gks208
DO - 10.1093/nar/gks208
M3 - Article
C2 - 22383582
AN - SCOPUS:84863219543
VL - 40
SP - 5766
EP - 5774
JO - Nucleic Acids Research
JF - Nucleic Acids Research
SN - 0305-1048
IS - 12
ER -