论文标题
细菌鞭毛细丝缠结的几何约束
Geometrical constraints on the tangling of bacterial flagellar filaments
论文作者
论文摘要
许多种类的细菌通过旋转多个螺旋鞭毛在粘性环境中游泳。细丝聚集在细胞体后面，并形成一个近螺旋束，在“运行”过程中推动细胞向前推动细胞。如果它们彼此纠结，捆绑包内的细丝也不能连续地驱动，也不能轻易解开。细菌可以被动形成连贯的束，即不包含缠结的细丝的束，鉴于鞭毛是由不协调的电动机驱动的，这一事实似乎令人惊讶。在本文中，我们建立了理论条件，在这些条件下，一对刚性的螺旋细丝可以形成一个纠结的束，并将这些约束与从文献中收集的实验数据进行了比较。我们的结果表明，细菌鞭毛太直，太远，无法基于其内在的，未呈现的几何形状形成纠结的束。这使得相干束的形成更加坚固，以抵制捆绑过程的被动性质，在这种情况下，单个细丝的位置无法控制。
Many species of bacteria swim through viscous environments by rotating multiple helical flagella. The filaments gather behind the cell body and form a close helical bundle, which propels the cell forward during a "run". The filaments inside the bundle cannot be continuously actuated, nor can they easily unbundle, if they are tangled around one another. The fact that bacteria can passively form coherent bundles, i.e. bundles which do not contain tangled pairs of filaments, may appear surprising given that flagella are actuated by uncoordinated motors. In this article, we establish the theoretical conditions under which a pair of rigid helical filaments can form a tangled bundle, and we compare these constraints with experimental data collected from the literature. Our results suggest that bacterial flagella are too straight and too far apart to form tangled bundles based on their intrinsic, undeformed geometry alone. This makes the formation of coherent bundles more robust against the passive nature of the bundling process, where the position of individual filaments cannot be controlled.
