Antonini Giulia, Civera Monica, Lal Kanhaya, Mazzotta Sarah, Varrot Annabelle, Bernardi Anna, Belvisi Laura
Università degli Studi di Milano, Dipartimento di Chimica, Milano, Italy.
Univ. Grenoble Alpes, CERMAV, CNRS, Grenoble, France.
Front Mol Biosci. 2023 May 31;10:1201630. doi: 10.3389/fmolb.2023.1201630. eCollection 2023.
Opportunistic infections from multidrug-resistant pathogens such as are a threatening risk for hospital-bound patients suffering from immunocompromised conditions or cystic fibrosis. BC2L-C lectin has been linked to bacterial adhesion and biofilm formation, thus hindering its activity is seen as a promising strategy to reduce the severity of the infection. We recently described the first bifunctional ligands of the trimeric N-terminal domain of BC2L-C (BC2L-C-Nt), capable of simultaneously engaging its fucose-specific sugar binding site and a vicinal region at the interface between two monomers. Here, we report a computational workflow for the study of these glycomimetic bifunctional ligands in complex with BC2L-C-Nt, aimed at investigating the molecular basis of ligand binding and the dynamics of glycomimetic/lectin interactions. In particular, we evaluated the use of molecular docking in the protein trimer, followed by refinement using MM-GBSA re-scoring and MD simulations in explicit water. Computational results were compared to experimental data derived from X-ray crystallography and isothermal titration calorimetry. The computational protocol proved suitable to provide a reliable description of the interactions between the ligands and BC2L-C-Nt, highlighting the contribution of MD simulations in explicit solvent for a good fit with the experimental observations. The information achieved in the study and the whole workflow appear promising for the structure-based design of improved BC2L-C-Nt ligands as novel antimicrobials with antiadhesive properties.
诸如多重耐药病原体引起的机会性感染,对于患有免疫功能低下疾病或囊性纤维化的住院患者来说是一种威胁性风险。BC2L-C凝集素与细菌黏附和生物膜形成有关,因此抑制其活性被视为减轻感染严重程度的一种有前景的策略。我们最近描述了BC2L-C三聚体N端结构域(BC2L-C-Nt)的首个双功能配体,它能够同时结合其岩藻糖特异性糖结合位点以及两个单体之间界面处的相邻区域。在此,我们报告了一个用于研究这些拟糖双功能配体与BC2L-C-Nt复合物的计算工作流程,旨在探究配体结合的分子基础以及拟糖/凝集素相互作用的动力学。特别是,我们评估了在蛋白质三聚体中使用分子对接,随后使用MM-GBSA重新评分和在显式水中进行分子动力学模拟进行优化。将计算结果与来自X射线晶体学和等温滴定量热法的实验数据进行了比较。该计算方案被证明适用于可靠描述配体与BC2L-C-Nt之间的相互作用,突出了在显式溶剂中进行分子动力学模拟对于与实验观察结果良好拟合的贡献。该研究中获得的信息以及整个工作流程对于基于结构设计改进的BC2L-C-Nt配体作为具有抗黏附特性的新型抗菌剂似乎很有前景。