Health & Environmental Research Online (HERO)


Print Feedback Export to File
7614551 
Journal Article 
Sequence selective photoinduced electron transfer of a pyrene-porphyrin dyad to DNA 
Heo, ME; Lee, YA; Hirakawa, K; Okazaki, S; Kim, SK; Cho, DW; , 
2018 
1 
Physical Chemistry Chemical Physics
ISSN: 1463-9076
EISSN: 1463-9084 
ROYAL SOC CHEMISTRY 
CAMBRIDGE 
20 
24 
16386-16392 
English 
29873346 
WOS:000436032900008 
The binding modes of a pyrene-porphyrin dyad, (1-pyrenyl)-tris(N-methyl-p-pyridino)porphyrin (PyTMpyP), to various DNAs (calf thymus DNA (Ct-DNA), poly[d(G-C)2], and poly[d(A-T)2]) have been investigated using circular dichroism and linear dichroism measurements. Based on the polarization spectroscopic results, it can be shown that the pyrenyl and porphryin planes are skewed to a large extent for PyTMPyP in an aqueous environment and in the binding site of poly[d(G-C)2]. In this complex, a photoinduced electron transfer (PET) process between the pyrenyl and porphyrin moieties occurs. On the other hand, PET was not observed in the PyTMPyP-poly[d(A-T)2] complex, whereas the fluorescence intensity of TMPyP was enhanced. The molecular planes of the pyrene and porphyrin moieties are almost parallel in the poly[d(A-T)2] and Ct-DNA adducts. Moreover, the generation of 1O2 species occurs only for the PyTMPyP-Ct-DNA and PyTMPyP-poly[d(A-T)2] complexes. We discuss the photophysical properties of PyTMPyP which are attributed to the binding patterns and the sequence of DNA bases.