Zilkenat Susann, Grin Iwan, Wagner Samuel
Biol Chem. 2017 Feb 1;398(2):155-164. doi: 10.1515/hsz-2016-0251.
Gaining knowledge of the structural makeup of protein complexes is critical to advance our understanding of their formation and functions. This task is particularly challenging for transmembrane protein complexes, and grows ever more imposing with increasing size of these large macromolecular structures. The last 10 years have seen a steep increase in solved high-resolution membrane protein structures due to both new and improved methods in the field, but still most structures of large transmembrane complexes remain elusive. An important first step towards the structure elucidation of these difficult complexes is the determination of their stoichiometry, which we discuss in this review. Knowing the stoichiometry of complex components not only answers unresolved structural questions and is relevant for understanding the molecular mechanisms of macromolecular machines but also supports further attempts to obtain high-resolution structures by providing constraints for structure calculations.
了解蛋白质复合物的结构组成对于深化我们对其形成和功能的理解至关重要。对于跨膜蛋白复合物而言，这项任务极具挑战性，并且随着这些大型大分子结构规模的不断增大，难度也日益增加。由于该领域新方法和改进方法的出现，过去十年中已解析出的高分辨率膜蛋白结构急剧增加，但大多数大型跨膜复合物的结构仍然难以确定。确定这些难解析复合物的化学计量比是阐明其结构的重要第一步，我们将在本综述中对此进行讨论。了解复合物组分的化学计量比不仅能解答尚未解决的结构问题，对于理解大分子机器的分子机制具有重要意义，还能为结构计算提供限制条件，从而支持进一步获取高分辨率结构的尝试。
