The unique characteristics of DNA charge transport (CT) have prompted an examination of roles for this chemistry within a biological context. Not only can DNA CT facilitate long-range oxidative damage of DNA, but redox-active proteins can couple to the DNA base stack and participate in long-range redox reactions using DNA CT. DNA transcription factors with redox-active moieties such as SoxR and p53 can use DNA CT as a form of redox sensing. DNA CT chemistry also provides a means to monitor the integrity of the DNA, given the sensitivity of DNA CT to perturbations in base stacking as arise with mismatches and lesions. Enzymes that utilize this chemistry include an interesting and ever-growing class of DNA-processing enzymes involved in DNA repair, replication, and transcription that have been found to contain 4Fe-4S clusters. DNA repair enzymes containing 4Fe-4S clusters, that include endonuclease III (EndoIII), MutY, and DinG from bacteria, as well as XPD from archaea, have been shown to be redox-active when bound to DNA, share a DNA-bound redox potential, and can be reduced and oxidized at long-range via DNA CT. Interactions between DNA and these proteins in solution, in addition to genetics experiments within Escherichia coli, suggest that DNA-mediated CT can be used as a means of cooperative signaling among DNA repair proteins that contain 4Fe-4S clusters as a first step in finding DNA damage, even within cells. On the basis of these data, we can consider also how DNA-mediated CT may be used as a means of signaling to coordinate DNA processing across the genome.
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机译：DNA电荷传输（CT）的独特特征促使人们在生物学背景下研究这种化学作用。 DNA CT不仅可以促进DNA的远距离氧化损伤，而且氧化还原活性蛋白可以偶联到DNA碱基堆栈上，并使用DNA CT参与远距离氧化还原反应。具有氧化还原活性部分的DNA转录因子（例如SoxR和p53）可以使用DNA CT作为氧化还原感测的一种形式。鉴于DNA CT对错配和损伤引起的碱基堆积扰动的敏感性，DNA CT化学也提供了一种监测DNA完整性的方法。利用这种化学作用的酶包括与DNA修复，复制和转录有关的有趣且不断增长的一类DNA处理酶，这些酶已被发现含有4Fe-4S簇。含有4Fe-4S簇的DNA修复酶，包括细菌中的核酸内切酶III（EndoIII），MutY和DinG，以及古细菌中的XPD，与DNA结合时具有氧化还原活性，并具有与DNA结合的氧化还原作用。可以通过DNA CT在远距离还原和氧化。 DNA和溶液中这些蛋白质之间的相互作用，以及在大肠杆菌内进行的遗传学实验表明，DNA介导的CT可以用作包含4Fe-4S簇的DNA修复蛋白之间的协作信号传递手段，这是寻找DNA的第一步甚至在细胞内也有损害。根据这些数据，我们还可以考虑如何将DNA介导的CT作为信号来协调整个基因组中DNA的加工。
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