NEITHER DELTA-TRIS(PHENANTHROLINE)RUTHENIUM(II) NOR LAMBDA-TRIS(PHENANTHROLINE)RUTHENIUM(II) BINDS TO DNA BY CLASSICAL INTERCALATION
NEITHER DELTA-TRIS(PHENANTHROLINE)RUTHENIUM(II) NOR LAMBDA-TRIS(PHENANTHROLINE)RUTHENIUM(II) BINDS TO DNA BY CLASSICAL INTERCALATION
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DOI：
10.1021/bi00154a001
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发表时间：
1992-10-06
期刊：
影响因子：
2.9
通讯作者：
CHAIRES, JB
中科院分区：
文献类型：
--
作者：
SATYANARAYANA, S;DABROWIAK, JC;CHAIRES, JB
平衡结合研究和粘度实验的特点DELTA-和LAMBDA-[Ru（o-phen）3]2+与小牛胸腺DNA的相互作用。这些化合物与DNA的结合方式是一个有争议的问题。发现[Ru（o-phen）3]2+的两种异构体都与DNA结合，但结合较弱，在20 ℃下，在含有5 mM Tris-HCl（pH 7.1）和10 mM NaCl的溶液中，DELTA和LAMBDA异构体的结合常数分别为4.9（+/-0.3）× 10（4）M-1和2.8（+/-0.2）× 10（4）M-1。我们确定DELTA和LAMBDA同分异构体的δ log K/δ log [Na+]分别等于1.37和1.24。应用静电理论，我们可以用这些值来定量地表明DELTA和LAMBDA异构体基本上都与DNA静电结合。粘度实验表明，结合LAMBDA异构体不会改变DNA的相对粘度到任何明显的程度，而结合DELTA异构体降低DNA的相对粘度。从这些粘度的结果，我们得出结论，没有异构体的[Ru（o-phen）3]2+结合到DNA的经典嵌入。
Equilibrium binding studies and viscosity experiments are described that characterize the interaction of DELTA- and LAMBDA-[Ru(o-phen)3]2+ with calf thymus DNA. The mode of binding of these compounds to DNA is a matter of controversy. Both isomers of [Ru(o-phen)3]2+ were found to bind but weakly to DNA, with binding constants of 4.9 (+/-0.3) X 10(4) M-1 and 2.8 (+/-0.2) X 10(4) M-1 determined for the DELTA and LAMBDA isomers, respectively, at 20-degrees-C in a solution containing 5 mM Tris-HCl (pH 7.1) and 10 mM NaCl. We determined that the quantity delta log K/delta log [Na+] equals 1.37 and 1.24 for the DELTA and LAMBDA isomers, respectively. Application of polyelectrolyte theory allows us to use these values to show quantitatively that both the DELTA and LAMBDA isomers are essentially electrostatically bound to DNA. Viscosity experiments show that binding the LAMBDA isomer does not alter the relative viscosity of DNA to any appreciable extent, while binding of the DELTA isomer decreases the relative viscosity of DNA. From these viscosity results, we conclude that neither isomer of [Ru(o-phen)3]2+ binds to DNA by classical intercalation.