Mårtensson Anna K F, Lincoln Per
Department of Chemical and Biological Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
Dalton Trans. 2015 Feb 28;44(8):3604-13. doi: 10.1039/c4dt02642j.
Linear and circular dichroism (LD and CD) spectroscopy as well as isothermal titration calorimetry (ITC) have been used to investigate the interaction of Ru(tpy)(py)dppz(2+) (tpy = 2,2':6',2''-terpyridyl; py = pyridine; dppz = dipyrido[3,2-a:2'3'-c]phenazine) with DNA, providing detailed information about the DNA binding thermodynamics and binding geometry of the metal complex. Flow LD, CD and isotropic absorption indicate that Ru(tpy)(py)dppz(2+) bind to DNA from the minor groove with the dppz ligand intercalated between base pairs, very similar to its chiral structural isomers Δ- and Λ-Ru(bpy)2dppz(2+) (bpy = 2,2'-bipyridine). A simple cooperative binding model with one binding geometry provide an excellent fit for calorimetric and absorption titration data. The values of the neighbor interaction thermodynamic parameters for Ru(tpy)(py)dppz(2+) suggest that complexes bound contiguously prefer to have their tpy ligands oriented towards the same strand.
线性和圆二色性（LD和CD）光谱以及等温滴定量热法（ITC）已被用于研究Ru(tpy)(py)dppz(2+)（tpy = 2,2':6',2''-三联吡啶；py = 吡啶；dppz = 二吡啶并[3,2-a:2'3'-c]吩嗪）与DNA的相互作用，提供了有关金属配合物的DNA结合热力学和结合几何结构的详细信息。流动LD、CD和各向同性吸收表明，Ru(tpy)(py)dppz(2+)从小沟与DNA结合，dppz配体插入碱基对之间，这与其手性结构异构体Δ-和Λ-Ru(bpy)2dppz(2+)（bpy = 2,2'-联吡啶）非常相似。具有一种结合几何结构的简单协同结合模型能很好地拟合量热和吸收滴定数据。Ru(tpy)(py)dppz(2+)的相邻相互作用热力学参数值表明，连续结合的配合物倾向于使其tpy配体朝向同一链。
