Kinematics of the swimming of Spiroplasma.
Kinematics of the swimming of Spiroplasma.
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DOI：
10.1103/physrevlett.102.218102
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发表时间：
2009-05
影响因子：
8.6
通讯作者：
Jing Yang;C. Wolgemuth;G. Huber
中科院分区：
文献类型：
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作者：
Jing Yang;C. Wolgemuth;G. Huber
采用基于阻力理论的简单模型对螺旋体游泳进行了研究。具体地说，我们考虑了一种螺旋形的细菌，它传播行波扭曲，从而反转螺旋细胞体的左手。我们把单元长度、节距角、扭结速度和扭结之间的距离作为参数，计算了由于扭曲而产生的游泳速度。我们发现，对于固定的俯仰角，缩放使游泳速度(和游泳效率)折叠成一条通用曲线，该曲线仅取决于扭结之间的距离与单元长度的比率。同时对节间长度和俯仰角进行了优化，得到最优俯仰角为35.5度，最佳节间长度比为0.338，与实验结果吻合较好。
Spiroplasma swimming is studied with a simple model based on resistive-force theory. Specifically, we consider a bacterium shaped in the form of a helix that propagates traveling-wave distortions which flip the handedness of the helical cell body. We treat cell length, pitch angle, kink velocity, and distance between kinks as parameters and calculate the swimming velocity that arises due to the distortions. We find that, for a fixed pitch angle, scaling collapses the swimming velocity (and the swimming efficiency) to a universal curve that depends only on the ratio of the distance between kinks to the cell length. Simultaneously optimizing the swimming efficiency with respect to interkink length and pitch angle, we find that the optimal pitch angle is 35.5 degrees and the optimal interkink length ratio is 0.338, values in good agreement with experimental observations.