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Reversal of a Single Base-Pair Step Controls Guanine Photo-Oxidation by an Intercalating Ruthenium(II) Dipyridophenazine Complex.

ABSTRACT: Small changes in DNA sequence can often have major biological effects. Here the rates and yields of guanine photo-oxidation by ?-[Ru(TAP)2(dppz)](2+) have been compared in 5'-{CCGGATCCGG}2 and 5'-{CCGGTACCGG}2 using pico/nanosecond transient visible and time-resolved IR (TRIR) spectroscopy. The inefficiency of electron transfer in the TA sequence is consistent with the 5'-TA-3' versus 5'-AT-3' binding preference predicted by X-ray crystallography. The TRIR spectra also reveal the differences in binding sites in the two oligonucleotides.

SUBMITTER: Keane PM

PROVIDER: S-EPMC4985698 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Reversal of a Single Base-Pair Step Controls Guanine Photo-Oxidation by an Intercalating Ruthenium(II) Dipyridophenazine Complex.

Keane Páraic M PM Poynton Fergus E FE Hall James P JP Sazanovich Igor V IV Towrie Michael M Gunnlaugsson Thorfinnur T Quinn Susan J SJ Cardin Christine J CJ Kelly John M JM

Angewandte Chemie (International ed. in English) 20150611 29

Small changes in DNA sequence can often have major biological effects. Here the rates and yields of guanine photo-oxidation by Λ-[Ru(TAP)2(dppz)](2+) have been compared in 5'-{CCGGATCCGG}2 and 5'-{CCGGTACCGG}2 using pico/nanosecond transient visible and time-resolved IR (TRIR) spectroscopy. The inefficiency of electron transfer in the TA sequence is consistent with the 5'-TA-3' versus 5'-AT-3' binding preference predicted by X-ray crystallography. The TRIR spectra also reveal the differences in ...[more]

PMID: 26096623

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