In:
Science, American Association for the Advancement of Science (AAAS), Vol. 322, No. 5899 ( 2008-10-10), p. 243-245
Abstract:
The high photostability of DNA is commonly attributed to efficient radiationless electronic relaxation processes. We used femtosecond time-resolved fluorescence spectroscopy to reveal that the ensuing dynamics are strongly dependent on base sequence and are also affected by higher-order structure. Excited electronic state lifetimes in dG-doped d(A) 20 single-stranded DNA and dG·dC-doped d(A) 20 ·d(T) 20 double-stranded DNA decrease sharply with the substitution of only a few bases. In duplexes containing d(AGA)·d(TCT) or d(AG)·d(TC) repeats, deactivation of the fluorescing states occurs on the subpicosecond time scale, but the excited-state lifetimes increase again in extended d(G) runs. The results point at more complex and molecule-specific photodynamics in native DNA than may be evident in simpler model systems.
Type of Medium:
Online Resource
ISSN:
0036-8075
,
1095-9203
DOI:
10.1126/science.1161651
Language:
English
Publisher:
American Association for the Advancement of Science (AAAS)
Publication Date:
2008
detail.hit.zdb_id:
128410-1
detail.hit.zdb_id:
2066996-3
detail.hit.zdb_id:
2060783-0
SSG:
11
