Interplay of surface interaction and magnetic torque in single-cell motion of magnetotactic bacteria in microfluidic confinement
- Max Planck Institute of Colloids and Interfaces, Germany
- CEA Cadarache, France
- University of Göttingen, Germany
Abstract
Swimming microorganisms often experience complex environments in their natural habitat. The same is true for microswimmers in envisioned biomedical applications. The simple aqueous conditions typically studied in the lab differ strongly from those found in these environments and often exclude the effects of small volume confinement or the influence that external fields have on their motion. In this work, we investigate magnetically steerable microswimmers, specifically magnetotactic bacteria, in strong spatial confinement and under the influence of an external magnetic field. We trap single cells in micrometer-sized microfluidic chambers and track and analyze their motion, which shows a variety of different trajectories, depending on the chamber size and the strength of the magnetic field. Combining these experimental observations with simulations using a variant of an active Brownian particle model, we explain the variety of trajectories by the interplay between the wall interactions and the magnetic torque. We also analyze the pronounced cell-to-cell heterogeneity, which makes single-cell tracking essential for an understanding of the motility patterns. In this way, our work establishes a basis for the analysis and prediction of microswimmer motility in more complex environments.
Data availability
All data (experimental and simulatedl trajectories) as well as analysis and simulation code has been deposited at Edmond, https://doi.org/10.17617/3.7b
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (KL 818/2-2)
- Stefan Klumpp
Deutsche Forschungsgemeinschaft (FA 835/7-2)
- Damien Faivre
BMBF and Max Planck Society (MaxSynBio)
- Tom Robinson
IMPRS on Multiscale Biosystems (n/a)
- Agnese Codutti
IMPRS on Multiscale Biosystems (n/a)
- Elisa Cerdá-Doñate
IMPRS on Multisclale Biosystems (n/a)
- Hubert M Taïeb
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Codutti 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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Interplay of surface interaction and magnetic torque in single-cell motion of magnetotactic bacteria in microfluidic confinement
eLife 11:e71527.
https://doi.org/10.7554/eLife.71527
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