Helical motion of the cell body enhances Caulobacter crescentus motility
Helical motion of the cell body enhances Caulobacter crescentus motility
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DOI：
10.1073/pnas.1407636111
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发表时间：
2014-08-05
影响因子：
11.1
通讯作者：
Breuer, Kenneth S.
中科院分区：
文献类型：
--
作者：
Liu, Bin;Gulino, Marco;Breuer, Kenneth S.
我们解决了3D轨迹和个别细胞的方向延长时间，使用数字跟踪技术结合3D重建。我们已经使用这种技术来研究单鞭毛细菌新月柄杆菌的运动性，并发现每个细胞显示两种不同的运动模式，这取决于鞭毛马达的旋转感。在前向模式中，当鞭毛推动细胞时，细胞体相对于运动方向倾斜，并且它进动，描绘出螺旋轨迹。在反向模式中，当鞭毛拉动细胞时，进动较小，并且细胞在每个旋转周期具有较低的平移距离，因此具有较低的运动性。利用阻力理论，我们展示了细胞体的螺旋运动如何产生推力，并可以解释游泳运动的方向依赖性变化。细胞体进动的来源被认为与连接鞭毛和细胞体的钩的柔性有关。
We resolve the 3D trajectory and the orientation of individual cells for extended times, using a digital tracking technique combined with 3D reconstructions. We have used this technique to study the motility of the uniflagellated bacterium Caulobacter crescentus and have found that each cell displays two distinct modes of motility, depending on the sense of rotation of the flagellar motor. In the forward mode, when the flagellum pushes the cell, the cell body is tilted with respect to the direction of motion, and it precesses, tracing out a helical trajectory. In the reverse mode, when the flagellum pulls the cell, the precession is smaller and the cell has a lower translation distance per rotation period and thus a lower motility. Using resistive force theory, we show how the helical motion of the cell body generates thrust and can explain the direction-dependent changes in swimming motility. The source of the cell body precession is believed to be associated with the flexibility of the hook that connects the flagellum to the cell body.