A new class of biological ion-driven rotary molecular motors with 5:2 symmetry.
A new class of biological ion-driven rotary molecular motors with 5:2 symmetry.
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DOI：
10.3389/fmicb.2022.948383
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发表时间：
2022
影响因子：
5.2
通讯作者：
中科院分区：
文献类型：
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作者：
通过冷冻电子显微镜 (cryo-EM) 获得并在 2019 年至 2021 年间发表的三种蛋白质复合物的几种新结构，确定了一个新的天然分子轮家族，即“5:2 旋转电机”。它们跨越细菌的细胞质膜，它们的旋转是由进入细胞的离子流驱动的。它们由革兰氏阳性和革兰氏阴性细菌细胞质膜内环绕二聚体轴的五聚体轮组成。轴延伸到周质中，轮延伸到细胞质中。从未直接观察到这些轮子的旋转；这是从复合体的对称性以及它们在已知的更大系统中所扮演的角色推断出来的。特别是，细菌鞭毛电机MotA5B2定子复合体的新结构与电机的“轮中轮”模型一致。其他 5:2 旋转电机被认为共享核心旋转功能和机制，由细胞质膜上的离子动力驱动。它们的结构在周质和细胞质部分有所不同，反映了它们所扮演的不同角色。本综述重点关注 5:2 旋转电机的结构及其提出的机制和功能。我们还讨论了一般的分子旋转及其与分子复合物旋转对称性的关系。
Several new structures of three types of protein complexes, obtained by cryo-electron microscopy (cryo-EM) and published between 2019 and 2021, identify a new family of natural molecular wheels, the “5:2 rotary motors.” These span the cytoplasmic membranes of bacteria, and their rotation is driven by ion flow into the cell. They consist of a pentameric wheel encircling a dimeric axle within the cytoplasmic membrane of both Gram-positive and gram-negative bacteria. The axles extend into the periplasm, and the wheels extend into the cytoplasm. Rotation of these wheels has never been observed directly; it is inferred from the symmetry of the complexes and from the roles they play within the larger systems that they are known to power. In particular, the new structure of the stator complex of the Bacterial Flagellar Motor, MotA5B2, is consistent with a “wheels within wheels” model of the motor. Other 5:2 rotary motors are believed to share the core rotary function and mechanism, driven by ion-motive force at the cytoplasmic membrane. Their structures diverge in their periplasmic and cytoplasmic parts, reflecting the variety of roles that they perform. This review focuses on the structures of 5:2 rotary motors and their proposed mechanisms and functions. We also discuss molecular rotation in general and its relation to the rotational symmetry of molecular complexes.
影响因子：
5.2
作者：
通讯作者：
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