Bacteria propel and change direction by rotating long, helical filaments, called flagella. The number of flagella, their arrangement on the cell body and their sense of rotation hypothetically determine the locomotion characteristics of a species. The movement of the most rapid microorganisms has in particular remained unexplored because of additional experimental limitations. We show that magnetotactic cocci with two flagella bundles on one pole swim faster than 500 µm·s-1 along a double helical path, making them one of the fastest natural microswimmers. We additionally reveal that the cells reorient in less than 5 ms, an order of magnitude faster than reported so far for any other bacteria. Using hydrodynamic modeling, we demonstrate that a mode where a pushing and a pulling bundle cooperate is the only possibility to enable both helical tracks and fast reorientations. The advantage of sheathed flagella bundles is the high rigidity, making high swimming speeds possible.
- Damien Faivre
- Damien Faivre
- Stefan Klumpp
- Sarah Mohammadinejad
- Stefan Klumpp
- Christopher T Lefèvre
- Agnese Codutti
The research leading to these results was supported by the Max Planck Society and by Deutsche Forschungsgemeinschaft (DFG) within the priority program on microswimmers (grants No. KL 818/2-2 and FA 835/7-2 to S.K. and D.F.). Further, S.M. was supported by Deutscher Akademischer Austauschdienst, DAAD (grant no. 57314018) as well as Deutsche Forschungsgemeinschaft (DFG) through SFB 937. A.C. is funded by the IMPRS on Multiscale Biosystems. C.T.L acknowledges support by the French National Research Agency (ANR Tremplin-ERC: ANR-16-TERC-0025-01).
- Raymond E Goldstein, University of Cambridge, United Kingdom
© 2020, Bente et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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