Protein-Controlled Actuation of Dynamic Nucleic Acid Networks by Using Synthetic DNA Translators**

Integrating dynamic DNA nanotechnology with protein-controlled actuation will expand our ability to process molecular information. We have developed a strategy to actuate strand displacement reactions using DNA-binding proteins by engineering synthetic DNA translators that convert specific protein-binding events into trigger inputs through a programmed conformational change. We have constructed synthetic DNA networks responsive to two different DNA-binding proteins, TATA-binding protein and Myc-Max, and demonstrated multi-input activation of strand displacement reactions. We achieved protein-controlled regulation of a synthetic RNA and of an enzyme through artificial DNA-based communication, showing the potential of our molecular system in performing further programmable tasks.     

Synthesis,DFT analysis and DNA studies,cytotoxicity and luminescence properties of a dinuclear copper(II) complex with 1,10-phenanthroline and 4-aminobenzoate

The dinuclear copper(II) complex, [Cu₂(phen)₂(4-aminobenzoate)₂(H₂O)₂](NO₃)₂·2(4-aminobenzoic acid)·3H₂O (phen = 1,10-phenanthroline), has been synthesized and structurally characterized by elemental analyses, IR, EPR, UV-visible and single-crystal X-ray crystallography. The complex crystallized in a monoclinic system with space group C2/c, a?=?26.0022(10) Å, b?=?10.2524(4) Å, c?=?20.9983(7) Å, α?=?90°, β?=?106.9550(10)° and γ?=?90°. The Cu(II) ion adopts a distorted square-pyramidal geometry formed by two N atoms from the phen ligand and two O atoms of the two 4-aminobenzoic acid ligands and one water O atom. The Cu…Cu separation is 3.0570(5) Å. A twofold axis passes through the midpoint of the Cu-Cu vector. The complex has intraligand (π–π*) fluorescence properties. The binding of this dinuclear copper(II) complex with calf thymus DNA (CT-DNA) was investigated by UV-vis absorption, fluorescence spectroscopic, cyclic voltammetric and viscosity techniques. Also, the cleavage of pBR322 DNA with dinuclear copper(II) complex was studied using gel electrophoresis method. The exhibited potent cytotoxic effects against human cell line (HepG2) and it was found to have good antimicrobial activities. The primary coordination sphere of dinuclear copper(II) complex is optimized, structural parameters are calculated and energy gaps of frontier orbital (HOMO-LUMO) have been calculated with B3LYP/6-31G/LANL2DZ level of theory in the gaseous phase. The calculated geometric and spectral results reproduced the experimental data with well agreement. Theoretical calculated molecular orbitals (HOMO-LUMO) and their energies have been calculated that suggest charge transfer occurs within the complex.     

[Ru（MeIm）4L]^2＋（L=iip，tip，2ntz）的电子结构、DNA-键合、构效关系及光谱特征

采用密度泛函的方法,结合导体极化连续模型研究了水溶性二价钌．甲基咪唑类配合物[Ru（MeIm）4iip]^2＋。（1）、[Ru（MeIm）4tip]^2＋0＋（2）和[Ru（MeIm）42ntz]^2＋（3）的电子结构、DNA的键合倾向及构效关系,在水溶液中几何优化的基础上分析了配合物的电子结构特征,并合理解释了配合物与DNA的键合倾向．计算结果表明,在主配体上用噻吩代替咪唑取代基可以有效提高配合物与DNA的键合力;同时,在主配体的骨架上引入强电负性的N原子及NO2基团可以明显降低配合物最低未占据分子轨道能量及前沿分子轨道能量差．基于以上计算结果,预测所设计的配合物3具有最大的DNA键合力常数．另外,详细分析了配合物1、2的构效关系及抗肿瘤作用机理,并预测了配合物3的抗肿瘤活性．最后,用含时密度泛函方法对配合物的电子吸收光谱进行了计算和模拟,并与实验结果进行了对比分析．     

基于席夫碱配体构筑的LnⅢ2配合物的结构、荧光性质及生物活性

以多齿席夫碱配体H₂L(H₂L=(E)-N′-(3-乙氧基-2-羟基亚苄基)-3-羟基吡啶甲酰肼)为配体,与Ln(acac)₃·2H₂O(Ln=Tb、Ho、Er;acac^-=乙酰丙酮根)反应,通过溶剂热法,成功得到了3例新的双核稀土配合物[Ln₂(acac)₂(L)₂(C₂H₅OH)₂](Ln=Tb((1)、Ho((2)、Er(3))。单晶X射线衍射分析表明：配合物1～3的结构主要由2个Ln^Ⅲ离子、2个乙酰丙酮根(acac^-)、2个L^2-及2个C₂H₅OH组成,中心Ln^Ⅲ离子通过2个μ₂-O原子相互连接,形成一个平行四边形的Ln₂O₂核心。固体荧光实验测...