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Deuterium isotope effect on excited-state dynamics in an alternating GC oligonucleotide.

ABSTRACT: Isotope effects on the excited-state dynamics of single- and double-stranded GC-containing DNAs were studied by femtosecond transient absorption spectroscopy. A pronounced deuterium isotope effect was observed in alternating d(GC)(9).d(GC)(9), but none was seen in the nonalternating or single-stranded variations investigated. These findings demonstrate that an interstrand process involving proton-coupled electron transfer contributes to the excited-state dynamics in DNAs having an appropriate base sequence.

SUBMITTER: de La Harpe K

PROVIDER: S-EPMC2792762 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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Deuterium isotope effect on excited-state dynamics in an alternating GC oligonucleotide.

de La Harpe Kimberly K Crespo-Hernández Carlos E CE Kohler Bern B

Journal of the American Chemical Society 20091201 48

Isotope effects on the excited-state dynamics of single- and double-stranded GC-containing DNAs were studied by femtosecond transient absorption spectroscopy. A pronounced deuterium isotope effect was observed in alternating d(GC)(9).d(GC)(9), but none was seen in the nonalternating or single-stranded variations investigated. These findings demonstrate that an interstrand process involving proton-coupled electron transfer contributes to the excited-state dynamics in DNAs having an appropriate ba ...[more]

PMID: 19950991

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