We report an exhaustive conformational and electronic study on dopamine (DA) interacting with the D2 dopamine receptor (D2DR). For the first time, the complete surface of the conformational potential energy of the complex DA/D2DR is reported. Such a surface was obtained through the use of QM/MM calculations. A detailed study of the molecular interactions that stabilize and destabilize the different molecular complexes was carried out using two techniques: Quantum Theory of Atoms in Molecules computations and nuclear magnetic shielding constants calculations. A comparative study of the behavior of DA in the gas phase, aqueous solution, and in the active site of D2DR has allowed us to evaluate the degree of deformation suffered by the ligand and, therefore, analyze how rustic are the lock‐key model and the induced fit theory in this case. Our results allow us to propose one of the conformations obtained as the “biologically relevant” conformation of DA when it is interacting with the D2DR.

中文翻译：

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多巴胺与 D2 多巴胺受体相互作用的构象和电子研究

我们报告了一项关于多巴胺 (DA) 与 D2 多巴胺受体 (D2DR) 相互作用的详尽构象和电子研究。首次报道了复合物 DA/D2DR 的构象势能的完整表面。这样的表面是通过使用 QM/MM 计算获得的。使用两种技术对稳定和破坏不同分子复合物的分子相互作用进行了详细研究：分子中原子的量子理论计算和核磁屏蔽常数计算。DA 在气相、水溶液和 D2DR 活性位点中的行为的比较研究使我们能够评估配体所遭受的变形程度，从而分析锁钥匙模型和在这种情况下，诱导拟合理论。