School of Pharmacy, Faculty of Natural Sciences, University of the Western Cape, Cape Town, South Africa; University of the Western Cape, Private Bag x17, Bellville, 7535, South Africa.
DSI/NRF Centre of Excellence for Biomedical Tuberculosis Research/South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, P.O. Box 241, Cape Town, 8000, South Africa.
Tuberculosis (Edinb). 2023 Jul;141:102350. doi: 10.1016/j.tube.2023.102350. Epub 2023 May 13.
A series of molecules containing bulky lipophilic scaffolds was screened for activity against Mycobacterium tuberculosis and a number of compounds with antimycobacterial activity were identified. The most active compound, (2E)-N-(adamantan-1-yl)-3-phenylprop-2-enamide (C1), has a low micromolar minimum inhibitory concentration, low cytotoxicity (therapeutic index = 32.26), low mutation frequency and is active against intracellular Mycobacterium tuberculosis. Whole genome sequencing of mutants resistant to C1 showed a mutation in mmpL3 which may point to the involvement of MmpL3 in the antimycobacterial activity of the compound. In silico mutagenesis and molecular modelling studies were performed to better understand the binding of C1 within MmpL3 and the role that the specific mutation may play in the interaction at protein level. These analyses revealed that the mutation increases the energy required for binding of C1 within the protein translocation channel of MmpL3. The mutation also decreases the solvation energy of the protein, suggesting that the mutant protein might be more solvent-accessible, thereby restricting its interaction with other molecules. The results reported here describe a new molecule that may interact with the MmpL3 protein, providing insights into the effect of mutations on protein-ligand interactions and enhancing our understanding of this essential protein as a priority drug target.
一系列含有大体积亲脂骨架的分子被筛选出对结核分枝杆菌有活性，发现了许多具有抗分枝杆菌活性的化合物。最活跃的化合物（2E）-N-（金刚烷-1-基）-3-苯基丙烯酰胺（C1）具有低微摩尔最低抑菌浓度、低细胞毒性（治疗指数=32.26）、低突变频率，并且对细胞内结核分枝杆菌有效。对 C1 耐药的突变体的全基因组测序显示 mmpL3 发生突变，这可能表明 MmpL3 参与了该化合物的抗分枝杆菌活性。进行了体内诱变和分子建模研究，以更好地了解 C1 在 MmpL3 内的结合情况，以及特定突变可能在蛋白质水平相互作用中所起的作用。这些分析表明，突变增加了 C1 在 MmpL3 蛋白易位通道内结合所需的能量。该突变还降低了蛋白质的溶剂化能，表明突变蛋白可能更容易溶剂化，从而限制了其与其他分子的相互作用。这里报道的结果描述了一种可能与 MmpL3 蛋白相互作用的新分子，为突变对蛋白-配体相互作用的影响提供了新的见解，并增强了我们对作为优先药物靶点的这种必需蛋白的理解。
