Systematic study of soft X-ray spectra of poly(Dg).poly(Dc) and poly(Da).poly(Dt) DNA duplexes.
In the present work, we have undertaken a combined experimental and theoretical study of X-ray spectroscopies for DNA base pairs, more precisely near-edge X-ray absorption, X-ray emission, and resonant inelastic X-ray scattering applied to poly(dG).poly(dC) and poly(dA).poly(dT) DNA duplexes. We have derived several conclusions on the nature of these X-ray spectra: the stacking of pairs has very little influence on the spectra; the spectra of a DNA composed of mixed Watson-Crick base pairs are well reproduced by linear combinations of GC and AT base pairs involved; the amine and imine nitrogens show noticeable differences as building blocks in the absorption, emission, and resonant emission spectra. The calculated spectra are in good agreement with experimental results. The ramifications of these conclusions for the use of X-ray spectroscopy for DNA are discussed.
Hua
Weijie
W
Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, S-106 91 Stockholm, Sweden.
Yamane
Hiroyuki
H
Gao
Bin
B
Jiang
Jun
J
Li
Shuhua
S
Kato
Hiroyuki S
HS
Kawai
Maki
M
Hatsui
Takaki
T
Luo
Yi
Y
Kosugi
Nobuhiro
N
Agren
Hans
H
D020029:Base Pairing; D004247:DNA / Q000737:chemistry*; D011067:Poly dA-dT / Q000737:chemistry*; D011089:Polydeoxyribonucleotides / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission
D011089:Polydeoxyribonucleotides; C016681:poly(dG).poly(dC); D011067:Poly dA-dT; D004247:DNA