NUCLEASE ACTIVITY OF 1,10-PHENANTHROLINE-COPPER ION

1，10-邻菲咯啉-亚铜络合物，(OP)2Cu+，过氧化氢为基团 辅酶反应，是一种人造核酸酶，它通过一种 生理pH和温度下的氧化途径。自.以来 反应通过核酸-(OP)2Cu+络合物进行，核酸酶是 取决于核酸的三维结构。为 例如，A-DNA的切割速度是B-DNA的1/7；单链和 Z-DNA对切割有抵抗力。由于(OP)2Cu+很小， 在结构紧凑的情况下，其核酸酶活性应由局部 DNA构象，不与卵裂远端碱基相互作用 地点。因此，(OP)2Cu+可能提供一种独特的方法来映射局部 DNA结构中可能在功能上重要的变异 遗传信息的表达。 这笔赠款的第一个目标是确定结构性决定因素。 通过研究DNA的消化模式来控制DNA的断裂 已知三维结构的寡核苷酸。然后，乳沟 不同的细菌操纵子将决定共同的结构特征 被(OP)2Cu+检测到。它们中引入的构象变化 将分析按突变和配体结合的区域。的范围 人工核酸酶活性将通过附着在 将1，10-二氮杂菲转化为DNA的特定配体 携带者进入位点特异性核酸酶。例如，op，绑定到 针对Z-DNA的抗体应该特别切断这一点 左撇子结构。最后，细胞内作用的效率 将对这种人造核酸酶进行探索，目的是检查 DNA原位结构和设计细胞类型特异性细胞毒剂。

1,10-Phenanthroline-cuprous complex, (OP)2Cu+, with hydrogen peroxide as a coreactant, is an artificial nuclease which cleaves DNA and RNA by an oxidative pathway at physiological pH's and temperatures. Since the reaction proceeds via a nucleic acid-(OP)2Cu+ complex, the nuclease is dependent on the three-dimensional structure of the nucleic acid. For example, A-DNA is cleaved at 1/7th the rate of B-DNA; single stranded and Z-DNA's are resistant to cleavage. Since (OP)2Cu+ is small and structurally compact, its nuclease activity should be governed by the local DNA conformation and not any interaction with bases distal to the cleavage site. Therefore, (OP)2Cu+ may provide a unique method to map the local variations in DNA structure that may be functionally important in the expression of genetic information. The first goal of this grant is to identify the structural determinants which control DNA scission by studying the digestion patterns of oligonucleotides of known three dimensional structure. Then, the cleavage of different bacterial operons will determine if common structural features are detected by (OP)2Cu+. Conformational changes introduced in these regions by mutations and ligand binding will be analyzed. The scope of the artificial nuclease activity will be enhanced by attaching 1,10-phenanthroline to specific ligands of DNA and converting these carriers into site specific nucleases. For example, OP, bound to antibodies directed against Z-DNA, should specifically nick this left-handed structure. Finally, the efficiency of the intracellular action of this artificial nuclease will be explored with the goals of examining DNA structure in situ and designing cell-type specific cytotoxic agents.