Intrinsic lifetimes of the excited state of DNA and RNA bases

被引：348

作者：

Kang, H ^{[1
]}

Lee, KT ^{[1
]}

Jung, B ^{[1
]}

Ko, YJ ^{[1
]}

Kim, SK ^{[1
]}

机构：

[1] Seoul Natl Univ, Sch Chem, Seoul 151747, South Korea

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2002年 / 124卷 / 44期

关键词：

D O I：

10.1021/ja027627x

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The lifetimes of the excited state of free nucleobases were measured in the gas phase for the first time. They are, respectively, 1.0 and 0.8 ps for the purine bases adenine (shown above) and guanine and 3.2, 2.4, and 6.4 ps for the pyrimidine bases cytosine, uracil, and thymine at 267 nm. The longer lifetimes of the pyrimidine bases may be associated with their higher propensity toward photodegradation, especially in the case of thymine. The ultrashort lifetime of nucleobases conventionally known in solution was found to be an intrinsic molecular property due to extremely facile internal conversion, and therefore the lifetime should be largely independent of the medium at this energy, that is, whether in vacuo, in solution, or in vivo. The evolutionary selection of nucleobases as the durable carriers of genetic information is suggested to be due to their inherent immunity from photochemical reactions. Copyright © 2002 American Chemical Society.

引用

页码：12958 / 12959

页数：2

共 26 条

[1]

BENSASSON RV, 1993, EXCITED STATES FREE, pCH5

[2] A theoretical investigation of the physical reason for the very different luminescence properties of the two isomers adenine and 2-aminopurine [J].