Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, 11158 Belgrade, Serbia.
J Phys Chem B. 2020 Apr 16;124(15):3002-3014. doi: 10.1021/acs.jpcb.0c01165. Epub 2020 Apr 1.
The possibility to target noncanonical guanine structures with specific ligands for therapeutic purposes inspired numerous theoretical and experimental investigations of a guanine quartet and its stacked composites. In this work, we employed the interacting quantum atoms methodology to study interactions among different fragments in complexes composed of a guanine quartet and alkali (Li, Na, K) or alkaline earth (Be, Mg, Ca) cations in vacuo: metal-quartet interaction, influence of the cation on guanine-guanine interaction, as well as hydrogen bond cooperativity in the guanine quartet and its complexes with metal ions. Interestingly, although the presence of a cation intensifies interaction among guanine molecules, it lowers their binding energy because of notable quartet's distortion which is responsible for guanines' substantial deformation energy. This phenomenon is particularly pronounced with Be which, out of the six analyzed cations, enhances hydrogen bond cooperativity to the greatest extent.
靶向具有特定配体的非规范鸟嘌呤结构用于治疗目的的可能性激发了对鸟嘌呤四重体及其堆叠复合材料的大量理论和实验研究。在这项工作中，我们采用了相互作用量子原子方法来研究由鸟嘌呤四重体和碱（Li、Na、K）或碱土（Be、Mg、Ca）阳离子组成的复合物中不同片段之间的相互作用：金属-四重体相互作用、阳离子对鸟嘌呤-鸟嘌呤相互作用的影响，以及鸟嘌呤四重体及其与金属离子形成的配合物中的氢键协同作用。有趣的是，尽管阳离子的存在会加剧鸟嘌呤分子之间的相互作用，但由于四重体的明显变形，会降低它们的结合能，这是导致鸟嘌呤变形能显著增加的原因。这种现象在 Be 中尤为明显，在分析的六种阳离子中，Be 最大程度地增强了氢键协同作用。
