A numerical method for the locomotion of bi-flagellated bacteria in viscous fluid
Flagellated bacteria propel themselves by rotating flexible flagella driven by independent motors. Depending on the rotation direction of the motors and the handedness of the helical filaments, the flagella either pull or push the cell body. Motivated by experimental observations of Magnetococcus ma...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Cambridge University Press
2023-01-01
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| Series: | Flow |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S2633425922000344/type/journal_article |
| _version_ | 1811156308310622208 |
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| author | Vahid Nourian Henry Shum |
| author_facet | Vahid Nourian Henry Shum |
| author_sort | Vahid Nourian |
| collection | DOAJ |
| description | Flagellated bacteria propel themselves by rotating flexible flagella driven by independent motors. Depending on the rotation direction of the motors and the handedness of the helical filaments, the flagella either pull or push the cell body. Motivated by experimental observations of Magnetococcus marinus, we develop an elastohydrodynamic model to study the locomotion of a bi-flagellated bacterium with one puller flagellum and one pusher flagellum. In this model, the boundary integral technique and Kirchhoff rod model are employed respectively to calculate the hydrodynamic forces on the swimmer and model the elastic deformations of the flagella. Our numerical results demonstrate that the model bacterium travels along a double helical trajectory, which is consistent with the experimental observations. Varying the stiffness, orientations or positions of the flagella significantly changes the swimming characteristics. Notably, when either the applied torque is higher than a critical value or the flagellum stiffness is lower than a critical stiffness, the pusher flagellum exhibits overwhirling motion, resulting in a more complicated swimming style and a lower swimming speed. For a moderate flagellum stiffness, the swimming speed is insensitive to the rest configuration orientation over a wide range of orientation angles as the flagella deform to maintain alignment with the swimming direction. |
| first_indexed | 2024-04-10T04:49:24Z |
| format | Article |
| id | doaj.art-77aa37e56bfe4cecb0331aea01761420 |
| institution | Directory Open Access Journal |
| issn | 2633-4259 |
| language | English |
| last_indexed | 2024-04-10T04:49:24Z |
| publishDate | 2023-01-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Flow |
| spelling | doaj.art-77aa37e56bfe4cecb0331aea017614202023-03-09T12:34:15ZengCambridge University PressFlow2633-42592023-01-01310.1017/flo.2022.34A numerical method for the locomotion of bi-flagellated bacteria in viscous fluidVahid Nourian0https://orcid.org/0000-0002-2230-9450Henry Shum1https://orcid.org/0000-0002-5385-1568Department of Applied Mathematics, University of Waterloo, Waterloo, ON N2L 3G1, CanadaDepartment of Applied Mathematics, University of Waterloo, Waterloo, ON N2L 3G1, CanadaFlagellated bacteria propel themselves by rotating flexible flagella driven by independent motors. Depending on the rotation direction of the motors and the handedness of the helical filaments, the flagella either pull or push the cell body. Motivated by experimental observations of Magnetococcus marinus, we develop an elastohydrodynamic model to study the locomotion of a bi-flagellated bacterium with one puller flagellum and one pusher flagellum. In this model, the boundary integral technique and Kirchhoff rod model are employed respectively to calculate the hydrodynamic forces on the swimmer and model the elastic deformations of the flagella. Our numerical results demonstrate that the model bacterium travels along a double helical trajectory, which is consistent with the experimental observations. Varying the stiffness, orientations or positions of the flagella significantly changes the swimming characteristics. Notably, when either the applied torque is higher than a critical value or the flagellum stiffness is lower than a critical stiffness, the pusher flagellum exhibits overwhirling motion, resulting in a more complicated swimming style and a lower swimming speed. For a moderate flagellum stiffness, the swimming speed is insensitive to the rest configuration orientation over a wide range of orientation angles as the flagella deform to maintain alignment with the swimming direction.https://www.cambridge.org/core/product/identifier/S2633425922000344/type/journal_articleMagnetococcus marinusFlexible flagellaViscous fluidRegularized Stokes formulationOverwhirling |
| spellingShingle | Vahid Nourian Henry Shum A numerical method for the locomotion of bi-flagellated bacteria in viscous fluid Flow Magnetococcus marinus Flexible flagella Viscous fluid Regularized Stokes formulation Overwhirling |
| title | A numerical method for the locomotion of bi-flagellated bacteria in viscous fluid |
| title_full | A numerical method for the locomotion of bi-flagellated bacteria in viscous fluid |
| title_fullStr | A numerical method for the locomotion of bi-flagellated bacteria in viscous fluid |
| title_full_unstemmed | A numerical method for the locomotion of bi-flagellated bacteria in viscous fluid |
| title_short | A numerical method for the locomotion of bi-flagellated bacteria in viscous fluid |
| title_sort | numerical method for the locomotion of bi flagellated bacteria in viscous fluid |
| topic | Magnetococcus marinus Flexible flagella Viscous fluid Regularized Stokes formulation Overwhirling |
| url | https://www.cambridge.org/core/product/identifier/S2633425922000344/type/journal_article |
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