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Updated: May 27, 2026
13:28
Introducing Shear Stress in the Study of Bacterial Adhesion
Published on: September 2, 2011
Reflections on a sticky situation: how surface contact pulls the trigger for bacterial adhesion.
Clare L Kirkpatrick1, Patrick H Viollier
1Department of Microbiology and Molecular Medicine, University of Geneva, 1 rue Michel-Servet, 1211 Geneva 4, Switzerland.
Molecular Microbiology
|November 19, 2011
Summary
Bacterial surface adhesion is regulated by cell cycle and surface contact. The flagellum acts as a mechanosensor, triggering holdfast production for irreversible attachment in Caulobacter crescentus.
Area of Science:
- Microbiology
- Cell Biology
- Biophysics
Background:
- Bacterial adhesion to surfaces is crucial for colonization and biofilm formation.
- Extracellular structures mediate bacterial attachment through specific or non-specific interactions.
- The sensory mechanisms regulating bacterial surface adhesion are not well understood.
Purpose of the Study:
- To investigate the regulation of bacterial adhesion and the transition from reversible to irreversible attachment.
- To examine the role of surface contact in adhesin production and holdfast formation in Caulobacter crescentus.
- To determine if the flagellum functions as a mechanosensor in the adhesion process.
Main Methods:
- Utilized Caulobacter crescentus as a model organism.
- Employed total internal reflection fluorescence (TIRF) microscopy to observe adhesion dynamics.
- Analyzed the cell cycle regulation and surface-induced responses related to adhesion.
Main Results:
- Adhesin production is under both developmental control and stimulated by surface contact.
- Initial reversible pili-surface contact leads to flagellum rotation arrest.
- Flagellum rotation arrest induces holdfast production, enabling irreversible adhesion.
Conclusions:
- Caulobacter crescentus produces holdfasts only when appropriate for surface attachment, preventing premature adhesin export.
- The flagellum acts as a critical mechanosensor, detecting surface contact and initiating irreversible adhesion.
- Surface adhesion in Caulobacter is a tightly regulated process involving cell cycle control and mechanical signaling.
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