| Summary: | 碩士 === 國立中興大學 === 生物化學研究所 === 87 === Abstract
The cleavage of DNA by vanadium(V)-preoxo complex under photo-irradiation conditions at neutral pH has been demonstrated (e.g., Inorg. Chem. 1997,36,1276-1277). In this study, we report the binding interaction between a vanadium(V)-peroxo complex, [VO(O2)2(5-NH2phen)] (where 5-NH2phen = 5-amino-1,10-phenanthroline), to seven synthetic oligo-nucleotides, 5’-GC-GATACC-GC---(I), 5’-GC-GGTATC-GC---(II), 5’-d(A)15---(IV) 5’-d(T)10---(V), 5’-AA-CCCCCC-TT---(VI) 5’-TT-GGGGGG-AA---(VII) and their mixture I+II、VI+VII, as well as a self-complementary oligermer 5’-GC-GATATC-GC---(III). The sequence-directed binding of oligo-DNA to vanadium(V)-peroxo complex was established. The fluorescence emission spectroscopy was used for monitoring the complex formation between vanadium(V)-preoxo complexes and DNA oligermers.
The substrate III contains the recognition sequence 5’-GATATC- but not in substrates I, II, IV, V, VI, VII. In this study, the fluorescence emission of this complex was found to be quenched by all the substrates, which give linear Stern-Volmer plots. For substrate (III)2 (Tm = 22 oC), static quenching was identified from the temperature-dependent quenching data. These results therefore indicate that a preferential binding interaction exists between the complex at the single-stranded and double-stranded form of III. In summary, evidence for a specific binding interaction between the [VO(O2)2(5-NH2phen)]- complex and an oligodeoxynucleotide (III) containing the sequence 5’-GATATC was found.
In addition, we also used CD spectroscopy and the UV/Visible spectroscopy demonstrated the duplex DNA that make form sample I+II、(III)2 and VI+VII which is B from duplex structure and the melting temperature(Tm) is near the room temperature.
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