Akdi Khalid, Vilaplana Rosario A, Kamah Sanae, González-Vílchez Francisco
Departamento de Química Inorgánica, Laboratorio de Química Bioinorgánica, Facultad de Química, Universidad de Sevilla, 41071 Sevilla, Spain.
J Inorg Biochem. 2005 Jun;99(6):1360-8. doi: 10.1016/j.jinorgbio.2005.03.010.
The Pd(II) complexes, [PdCl(2)(1,2-pn)] and [PdCl(2)(1,3-pn)] (pn is diaminopropane), were synthesized and characterized by analytical and spectroscopic (FT-IR, (1)H NMR and (13)C NMR) techniques. UV difference spectral study performed on Pd-pn/DNA systems, indicate a pronounced interaction of palladium complexes with DNA in cell-free media; comparison of lambda(max), Abs(max) and %H values observed for the two compounds might be attributed to structural differences of the chelated ligand rings. Results obtained from electrophoretic analysis of Pd complexes in presence of pBR322 plasmid DNA show a clear decreasing of the supercoiled (SC) DNA form mobility, that could be attributed to unwinding of the double helix; a parallel increasing of the open-circular (OC) DNA form mobility is also noted, this fact implying that the binding of complexes either shortens or condenses the DNA helix. Interaction studies of Pd complexes with plasmid DNA in different buffer systems indicate that DNA binding efficiency capable of modifying the tertiary structure of pBR322 decreased from NaClO(4) to Hepes 2, Hepes 1 [Hepes=4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid], and Tris [(hydroxymethyl)aminomethane] buffers, in this order. Moreover, the level of DNA modifications produced by palladium complexes in 10 mM NaClO(4) remains unchanged after transferring the samples into the medium required for subsequent biophysical or biochemical analyses.
合成了二价钯配合物[PdCl₂(1,2 - pn)]和[PdCl₂(1,3 - pn)]（pn为二氨基丙烷），并通过分析和光谱（傅里叶变换红外光谱、¹H核磁共振和¹³C核磁共振）技术对其进行了表征。对钯 - pn/DNA体系进行的紫外差光谱研究表明，钯配合物在无细胞培养基中与DNA有显著相互作用；观察到的两种化合物的最大吸收波长（λmax）、最大吸光度（Abs(max)）和%H值的比较可能归因于螯合配体环的结构差异。在pBR322质粒DNA存在下对钯配合物进行电泳分析得到的结果表明，超螺旋（SC）DNA形式的迁移率明显降低，这可能归因于双螺旋的解旋；同时也注意到开环（OC）DNA形式的迁移率平行增加，这一事实意味着配合物的结合要么缩短了DNA螺旋，要么使其凝聚。在不同缓冲体系中对钯配合物与质粒DNA的相互作用研究表明，能够改变pBR322三级结构的DNA结合效率从高到低依次为高氯酸钠、Hepes 2、Hepes 1 [Hepes = 4 - (2 - 羟乙基)-1 - 哌嗪乙磺酸]和Tris [三（羟甲基）氨基甲烷]缓冲液。此外，将样品转移到后续生物物理或生化分析所需的培养基中后，钯配合物在10 mM高氯酸钠中产生的DNA修饰水平保持不变。
