卟啉衍生物TMPyP4与单链DNA的结合机理研究

Binding Mechanism of meso-Tetrakis(4-) Porphyrin TMPyP4 with the Single-Strand DNA 5’-TTAGGG-3’ (1.School of Life Science, Beijing Institute of Technology, Beijing 100081, China; 2. School of Material Science and Engineering, Beijing Institute of

摘要: 通过圆二色谱、稳态吸收光谱、稳态荧光光谱和皮秒时间分辩荧光光谱研究了meso-四(4-(N-甲基吡啶基))卟啉(TMPyP4)与端粒DNA 5'-TTAGGG-3'(S6)的结合机理. 稳态光谱实验结果表明,在没有金属离子的Tris-HCl缓冲溶液中,S6 DNA以单链的形式存在,TMPyP4与单链DNA的结合常数为1.51×10⁶ (mol/L)^-1,饱和结合数为1.2. 通过时间分辨荧光光谱对二者相互作用的机理进行了进一步研究,推测了TMPyP4与单链S6 DNA之间的结合模式.

Abstract: The binding mechanism of meso-tetrakis(4-(N-methylpyridiumyl))porphyrin (TMPyP4) and the telomeric sequence DNA 5'-TTAGGG-3' (S6) has been explored by means of circular dichroism spectrum, steady-state absorption, steady-state fluorescence and picosecond time-resolved fluorescence spectrums. DNA adopts the single-strand conformation in Tris-HCl buffer without any metal ions. The binding constant and the saturated binding number between TMPyP4 and S6 DNA were determined as 1.51×10⁶ (mol/L)^-1 and 1.2, respectively, according to steady-state absorption spectroscopy. Furthermore, on the findings of time-resolved fluorescence spectroscopic technique, the binding modes can be presumed.