Srivastava Ruby
Bioinformatics, CSIR-Centre for Cellular and Molecular Biology, Hyderabad 500607, India.
ACS Omega. 2020 Jul 20;5(30):18808-18817. doi: 10.1021/acsomega.0c01931. eCollection 2020 Aug 4.
Nucleobase pair-metal dimer/dinuclear metal cation interactions play an important role in biological applications because of their highly symmetrical structures and high stabilities. In this work, we have selected five adenine-adenine hydrogen bonding, adenine-thymine (AT), adenine-uracil, adenine-adenine stacking pairs, and Watson-Crick AT stacking pairs and studied their interaction with the coinage metal dimer M and M metal cations, where M = Ag, Au, and Cu. Quantum chemical calculations have been carried out with density functional theory (DFT) and time-dependent DFT (TDDFT) methods. Electronic structures were analyzed by the partial density of states method. During interactions, we find that M-M distances are shorter than the sum of van der Waals radii of the corresponding two homocoinage metal atoms, which show the existence of significant metallophilic interactions. Results indicated that nucleobase-M complexes are stronger as compared to nucleobase-M complexes. Also, the replacement of the hydrogen bond by the dinuclear metal cation-coordinated bond forms more stable alternative metallo-DNA sequences in AAST base pairs. TDDFT calculations reveal that nucleobase-Cu complexes and nucleobase-Ag /Au complexes can be used for fluorescent markers and logic gate applications. Atom-in-molecules analysis predicted the noncovalent interaction in these complexes.
核碱基对 - 金属二聚体/双核金属阳离子相互作用因其高度对称的结构和高稳定性在生物应用中发挥着重要作用。在这项工作中，我们选择了五个腺嘌呤 - 腺嘌呤氢键、腺嘌呤 - 胸腺嘧啶（AT）、腺嘌呤 - 尿嘧啶、腺嘌呤 - 腺嘌呤堆积对以及沃森 - 克里克AT堆积对，并研究了它们与货币金属二聚体M₂和M⁺金属阳离子的相互作用，其中M = Ag、Au和Cu。采用密度泛函理论（DFT）和含时密度泛函理论（TDDFT）方法进行了量子化学计算。通过态密度方法分析了电子结构。在相互作用过程中，我们发现M - M距离短于相应两个同货币金属原子的范德华半径之和，这表明存在显著的亲金属相互作用。结果表明，与核碱基 - M络合物相比，核碱基 - M₂络合物更强。此外，双核金属阳离子配位键取代氢键在AAST碱基对中形成了更稳定的替代金属DNA序列。TDDFT计算表明，核碱基 - Cu络合物以及核碱基 - Ag⁺/Au⁺络合物可用于荧光标记和逻辑门应用。分子中的原子分析预测了这些络合物中的非共价相互作用。
