Kinosita Yoshiaki, Sowa Yoshiyuki
CPR, RIKEN, Wako, Saitama 351-0198, Japan.
Department of Frontier Bioscience, Hosei University, Tokyo 184-8584, Japan.
Biophys Physicobiol. 2023 May 30;20(2):e200024. doi: 10.2142/biophysico.bppb-v20.0024. eCollection 2023 Jun 14.
Most motile bacteria use supramolecular motility machinery called bacterial flagellum, which converts the chemical energy gained from ion flux into mechanical rotation. Bacterial cells sense their external environment through a two-component regulatory system consisting of a histidine kinase and response regulator. Combining these systems allows the cells to move toward favorable environments and away from their repellents. A representative example of flagellar motility is run-and-tumble swimming in , where the counter-clockwise (CCW) rotation of a flagellar bundle propels the cell forward, and the clockwise (CW) rotation undergoes cell re-orientation (tumbling) upon switching the direction of flagellar motor rotation from CCW to CW. In this mini review, we focus on several types of chemotactic behaviors that respond to changes in flagellar shape and direction of rotation. Moreover, our single-cell analysis demonstrated back-and-forth swimming motility of an original strain. We propose that polymorphic flagellar changes are required to enhance bacterial movement in a structured environment as a colony spread on an agar plate.
大多数运动性细菌利用一种称为细菌鞭毛的超分子运动机制，该机制将离子通量获得的化学能转化为机械旋转。细菌细胞通过由组氨酸激酶和反应调节因子组成的双组分调节系统感知其外部环境。将这些系统结合起来使细胞能够向有利环境移动并远离驱避剂。鞭毛运动的一个典型例子是在大肠杆菌中的“游动-翻滚”游泳，其中鞭毛束的逆时针（CCW）旋转推动细胞向前，而顺时针（CW）旋转在将鞭毛马达旋转方向从CCW切换到CW时使细胞重新定向（翻滚）。在本综述中，我们重点关注几种响应鞭毛形状和旋转方向变化的趋化行为类型。此外，我们的单细胞分析证明了原始菌株的来回游动运动性。我们提出，在结构化环境中，如菌落扩散在琼脂平板上时，多态性鞭毛变化对于增强细菌运动是必需的。
