English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Dynamic force measurements on swimming Chlamydomonas cells using micropipette force sensors

Böddeker, T. J., Karpitschka, S. A., Kreis, C. T., Magdelaine, Q., & Bäumchen, O. (2020). Dynamic force measurements on swimming Chlamydomonas cells using micropipette force sensors. Interface: Journal of the Royal Society, 17: 20190580. doi:10.1098/rsif.2019.0580.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/21.11116/0000-0005-7B98-6 Version Permalink: http://hdl.handle.net/21.11116/0000-0005-80BF-3
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Böddeker, Thomas J.1, Author              
Karpitschka, Stefan A.2, Author              
Kreis, Christian Titus1, Author              
Magdelaine, Quentin1, Author              
Bäumchen, Oliver1, Author              
Affiliations:
1Group Dynamics of fluid and biological interfaces, Department of Dynamics of Complex Fluids, Max Planck Institute for Dynamics and Self-Organization, Max Planck Society, ou_2063300              
2Group Fluidics in heterogeneous environments, Department of Dynamics of Complex Fluids, Max Planck Institute for Dynamics and Self-Organization, Max Planck Society, ou_2466703              

Content

show
hide
Free keywords: Chlamydomonas; active matter; cell motility; flagella; force measurements; microswimmers
 Abstract: Flagella and cilia are cellular appendages that inherit essential functions of microbial life including sensing and navigating the environment. In order to propel a swimming microorganism they displace the surrounding fluid by means of periodic motions, while precisely timed modulations of their beating patterns enable the cell to steer towards or away from specific locations. Characterizing the dynamic forces, however, is challenging and typically relies on indirect experimental approaches. Here, we present direct in vivo measurements of the dynamic forces of motile Chlamydomonas reinhardtii cells in controlled environments. The experiments are based on partially aspirating a living microorganism at the tip of a micropipette force sensor and optically recording the micropipette’s position fluctuations with high temporal and sub-pixel spatial resolution. Spectral signal analysis allows for isolating the cell-generated dynamic forces caused by the periodic motion of the flagella from background noise. We provide an analytic, elasto-hydrodynamic model for the micropipette force sensor and describe how to obtain the micropipette’s full frequency response function from a dynamic force calibration. Using this approach, we measure the amplitude of the oscillatory forces during the swimming activity of individual Chlamydomonas reinhardtii cells of 26 ± 5 pN, resulting from the coordinated flagellar beating with a frequency of 49 ± 5 Hz. This dynamic micropipette force sensor technique generalizes the applicability of micropipettes as force sensors from static to dynamic force measurements, yielding a force sensitivity in the piconewton range. In addition to measurements in bulk liquid environment, we study the dynamic forces of the biflagellated microswimmer in the vicinity of a solid/liquid interface. As we gradually decrease the distance of the swimming microbe to the interface, we measure a significantly enhanced force transduction at distances larger than the maximum extent of the beating flagella, highlighting the importance of hydrodynamic interactions for scenarios in which flagellated microorganisms encounter surfaces.

Details

show
hide
Language(s): eng - English
 Dates: 2020-01-15
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Method: Peer
 Identifiers: DOI: 10.1098/rsif.2019.0580
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Interface : Journal of the Royal Society
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: London : Royal Society
Pages: 11 Volume / Issue: 17 Sequence Number: 20190580 Start / End Page: - Identifier: ISSN: 1742-5689
CoNE: https://pure.mpg.de/cone/journals/resource/1000000000018840_1