在过去15年中获得的bc1配合物的X射线晶体结构为我们对该配合物的理解提供了坚实的结构基础。在大多数情况下，来自不同物种的结构之间有很好的一致性，不同的晶体形式，并结合不同的抑制剂。在这篇综述中，我们重点讨论了一些剩余的无法解释的差异，在结构本身或结构观察的解释之间。这些包括Rieske铁硫蛋白响应抑制剂而运动的结构基础，可能涉及细胞色素（cyt）b的酪氨酸132的构象变化，在跨膜螺旋C的开始处存在顺式肽，E,H,对所谓“核心蛋白”功能的结构洞察，保留的信号肽的不同模型，低电位血红素b的取向，以及Met配体对血红素c1的手性。本文是特刊的一部分，标题为：呼吸复合物III和相关的BC复合物。
X-ray crystal structures of bc1 complexes obtained over the last 15 years have provided a firm structural basis for our understanding of the complex. For the most part there is good agreement between structures from different species, different crystal forms, and with different inhibitors bound. In this review we focus on some of the remaining unexplained differences, either between the structures themselves or the interpretations of the structural observations. These include the structural basis for the motion of the Rieske iron-sulfur protein in response to inhibitors, a possible conformational change involving tyrosine132 of cytochrome (cyt) b, the presence of cis-peptides at the beginnings of transmembrane helices C, E, and H, the structural insight into the function of the so-called \"Core proteins\", different modelings of the retained signal peptide, orientation of the low-potential heme b, and chirality of the Met ligand to heme c1. This article is part of a Special Issue entitled: Respiratory complex III and related bc complexes.
