Using metal complex reduced states to monitor the oxidation of DNA.
Using metal complex reduced states to monitor the oxidation of DNA.
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DOI：
10.1021/ic201511y
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发表时间：
2011-12-05
影响因子：
4.6
通讯作者：
Barton JK
中科院分区：
文献类型：
--
作者：
Olmon ED;Hill MG;Barton JK
金属嵌入光氧化剂与双链DNA基叠密切相互作用，并表现出丰富的光物理和电化学性质，使其成为研究DNA介导的电荷传输（CT）的理想探针。将配合物[Rh(phi)2(bpy ')]3+ （phi = 9,10-菲三醌二亚胺；bpy ' = 4-甲基-4 ' -（丁酸）-2,2 ' -联吡啶），[Ir(ppy)2(dppz ')]+ （ppy = 2-苯基吡啶；dppz ' = 6-（二吡啶[3,2-a:2 ',3 ' -c]吩那嗪-11-基）己-5-炔酸），和[Re(CO)3(dppz)(py ')]+ （dppz =二吡啶[2,3-a:2 ',3 ' -c]吩那嗪；py ' = 3-（吡啶-4-基）-丙酸）分别以共价拴在DNA上，比较它们的光氧化效率。生化研究表明，辐照后，三种配合物通过远程dna介导的CT氧化鸟嘌呤，其效率为：Rh > Re > Ir。通过对游离金属配合物进行体还原后的光谱与对共轭物进行瞬态吸收（TA）光谱的比较表明，共轭物在355nm激发后形成了还原金属态。电化学实验和动力学分析表明，CT的热力学驱动力、反向电子转移效率的变化以及与DNA的耦合是导致三种配合物的鸟嘌呤氧化产率变化趋势的主要因素。
Metallointercalating photooxidants interact intimately with the base stack of double-stranded DNA and exhibit rich photophysical and electrochemical properties, making them ideal probes for the study of DNA-mediated charge transport (CT). The complexes [Rh(phi)2(bpy′)]3+ (phi = 9,10-phenanthrenequinone diimine; bpy′ = 4-methyl-4′-(butyric acid)-2,2′-bipyridine), [Ir(ppy)2(dppz′)]+ (ppy = 2-phenylpyridine; dppz′ = 6-(dipyrido[3,2-a:2′,3′-c]phenazin-11-yl)hex-5-ynoic acid), and [Re(CO)3(dppz)(py′)]+ (dppz = dipyrido[2,3-a:2′,3′-c]phenazine; py′ = 3-(pyridin-4-yl)-propanoic acid) were each covalently tethered to DNA in order to compare their photooxidation efficiencies. Biochemical studies show that upon irradiation, the three complexes oxidize guanine by long-range DNA-mediated CT with the efficiency: Rh > Re > Ir. Comparison of spectra obtained by spectroelectrochemistry after bulk reduction of the free metal complexes with those obtained by transient absorption (TA) spectroscopy of the conjugates suggests that the reduced metal states form following excitation of the conjugates at 355 nm. Electrochemical experiments and kinetic analysis of the TA decays indicate that the thermodynamic driving force for CT, variations in the efficiency of back electron transfer, and coupling to DNA are the primary factors responsible for the trend observed in the guanine oxidation yield of the three complexes.
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影响因子：
15
作者：
Dohno, C;Stemp, EDA;Barton, JK
通讯作者：
Barton, JK
影响因子：
4.6
作者：
Delaney, S;Pascaly, M;Barton, JK
通讯作者：
Barton, JK
影响因子：
4.6
作者：
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通讯作者：
ZALIS, S
影响因子：
3.1
作者：
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通讯作者：
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影响因子：
4.3
作者：
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通讯作者：
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