Trinh Thi Kim Hoang, Cabezas Andres Jorge, Joshi Soumil, Catalano Claudio, Siddique Abu Bakkar, Qiu Weihua, Deshmukh Sanket, des Georges Amedee, Guo Youzhong
Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University Richmond VA 23298 USA
Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University Richmond VA 23219 USA.
Chem Sci. 2023 Jun 9;14(26):7310-7326. doi: 10.1039/d3sc01890c. eCollection 2023 Jul 5.
Accurate 3D structures of membrane proteins are essential for comprehending their mechanisms of action and designing specific ligands to modulate their activities. However, these structures are still uncommon due to the involvement of detergents in the sample preparation. Recently, membrane-active polymers have emerged as an alternative to detergents, but their incompatibility with low pH and divalent cations has hindered their efficacy. Herein, we describe the design, synthesis, characterization, and application of a new class of pH-tunable membrane-active polymers, NCMNP2a-. The results demonstrated that NCMNP2a- could be used for high-resolution single-particle cryo-EM structural analysis of AcrB in various pH conditions and can effectively solubilize TSPO with the function preserved. Molecular dynamic simulation is consistent with experimental data that shed great insights into the working mechanism of this class of polymers. These results demonstrated that NCMNP2a- might have broad applications in membrane protein research.
膜蛋白的精确三维结构对于理解其作用机制以及设计特定配体来调节其活性至关重要。然而，由于在样品制备过程中涉及去污剂，这些结构仍然并不常见。最近，膜活性聚合物已成为去污剂的替代品，但其与低pH值和二价阳离子的不相容性阻碍了其功效。在此，我们描述了一类新型的pH可调膜活性聚合物NCMNP2a-的设计、合成、表征及应用。结果表明，NCMNP2a-可用于在各种pH条件下对AcrB进行高分辨率单颗粒冷冻电镜结构分析，并且能够有效溶解TSPO并保留其功能。分子动力学模拟与实验数据一致，为这类聚合物的作用机制提供了深刻见解。这些结果表明，NCMNP2a-可能在膜蛋白研究中具有广泛应用。
