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In early stage of radiation-induced DNA damage,
high-energy radiation ionizes nucleic acid bases,
generating positive holes and electrons within DNA
strand. Identification of the DNA sites that trap
holes and electrons is essential to understanding
the process of DNA damage caused directly by ionizing radiation. The positive holes are trapped at
guanine (G) sites with lower oxidation potential on
the DNA helix. Similarly the electron trap sites
favoring e$cient transport of excess electrons in
DNA may be present.
Key words: DNA, radiation damage, hole, electron
transfer, proton transfer
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Migration and Trapping of Hole and Excess Electrons in
Double-Stranded DNA
Kazuo KD76N6H=>, Ryuhei Y6B6<6B>, and Seiichi T6<6L6
(The Institute of Scientific and Industrial Research, Osaka
University)
ῌ567ῌ0047 ·4¸56A¹ 8ῌ1
TEL: 06ῌ6879ῌ8501, FAX: 06ῌ6876ῌ3287
E-mail: kobayasi@sanken. osaka-u. ac. jp
º 86 » (2008)
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