Department of Physics, University of Science and Technology of China, Hefei 230026, China.
Proc Natl Acad Sci U S A. 2022 Apr 5;119(14):e2120508119. doi: 10.1073/pnas.2120508119. Epub 2022 Mar 29.
SignificanceThe monotrichous was usually thought to swim in a pattern of "run and reverse" (possibly with pauses in between), where straight runs alternated with reverses with angular changes of swimming direction near 180°. Here, by simultaneously tracking the cell swimming and the morphology of its flagellum, we discovered a swimming mode in -the wrap mode, during which the flagellar filament wrapped around the cell body and induced large fluctuation of the body orientation. The wrap mode randomized swimming direction, resulting in a broad distribution of angular changes over 0 to 180° with a peak near 90°. This allowed the bacterium to explore the environment more efficiently, which we confirmed by stochastic simulations of chemotaxis.
意义
通常认为，纤毛菌以“奔跑和反转”的模式游动（可能在两者之间有停顿），其中直线奔跑与以接近 180°的角度改变游动方向的反转交替出现。在这里，通过同时跟踪细胞的游动和其鞭毛的形态，我们发现了一种游动模式——缠绕模式，在此过程中，鞭毛丝缠绕在细胞体上，并引起细胞体方向的剧烈波动。缠绕模式使游动方向随机化，导致角度变化在 0 到 180°之间的广泛分布，峰值接近 90°。这使得细菌能够更有效地探索环境，我们通过化学趋性的随机模拟证实了这一点。
