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How flagellated bacteria wobble

Soft Condensed Matter 2026-05-29 v1 Biological Physics

Abstract

A flagellated bacterium navigates fluid environments by rotating its helical flagellar bundle. The wobbling of the bacterial body significantly influences its swimming behavior. To quantify the three underlying motions--precession, nutation, and spin, we extract the Euler angles from trajectories generated by mesoscale hydrodynamics simulations, which is experimentally unattainable. In contrast to the common assumption, the cell body does not undergo complete cycles of spin, a general result for multiflagellated bacteria. Our simulations produce apparent wobbling periods that closely match the results of {\it E. coli} obtained from experiments and reveal the presence of two kinds of precession modes, consistent with theoretical analysis. Small-amplitude yet periodic nutation is also observed in the simulations.

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Cite

@article{arxiv.2409.13350,
  title  = {How flagellated bacteria wobble},
  author = {Jinglei Hu and Chen Gui and Mingxin Mao and Pu Feng and Yurui Liu and Xiangjun Gong and Gerhard Gompper},
  journal= {arXiv preprint arXiv:2409.13350},
  year   = {2026}
}

Comments

3 figures

R2 v1 2026-06-28T18:51:10.121Z