NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584, CH Utrecht, The Netherlands.
MOE Key Lab for Cellular Dynamics, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, 230026, Anhui, China.
Angew Chem Int Ed Engl. 2022 Aug 15;61(33):e202203319. doi: 10.1002/anie.202203319. Epub 2022 Jul 7.
Membrane proteins are known to exert many essential biological functions by forming complexes in cell membranes. An example refers to the β-barrel assembly machinery (BAM), a 200 kDa pentameric complex containing BAM proteins A-E that catalyzes the essential process of protein insertion into the outer membrane of gram-negative bacteria. While progress has been made in capturing three-dimensional structural snapshots of the BAM complex, the role of the lipoprotein BamC in the complex assembly in functional lipid bilayers has remained unclear. We have devised a component-selective preparation scheme to directly study BamC as part of the entire BAM complex in lipid bilayers. Combination with proton-detected solid-state NMR methods allowed us to probe the structure, dynamics, and supramolecular topology of full-length BamC embedded in the entire complex in lipid bilayers. Our approach may help decipher how individual proteins contribute to the dynamic formation and functioning of membrane protein complexes in membranes.
膜蛋白通过在细胞膜中形成复合物来发挥许多重要的生物学功能。一个例子是β-桶组装机制（BAM），这是一个包含 BAM 蛋白 A-E 的 200 kDa 五聚体复合物，它催化蛋白质插入革兰氏阴性细菌外膜的基本过程。虽然已经在捕获 BAM 复合物的三维结构快照方面取得了进展，但脂蛋白 BamC 在功能性脂质双层中复合物组装中的作用仍不清楚。我们设计了一种组分选择性的制备方案，以直接在脂质双层中作为整个 BAM 复合物的一部分研究 BamC。与质子检测固态 NMR 方法相结合，使我们能够探测完整复合物中全长 BamC 的结构、动力学和超分子拓扑结构。我们的方法可能有助于破译单个蛋白质如何有助于膜蛋白复合物在膜中的动态形成和功能。
