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Biophysical Characterization of Flagellar Motor Functions
Published on: January 18, 2017
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Second messenger-mediated tactile response by a bacterial rotary motor
Isabelle Hug1, Siddharth Deshpande2, Kathrin S Sprecher1
1Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH-4056, Switzerland.
Science (New York, N.Y.)
|October 28, 2017
Summary
Bacteria sense surfaces using their flagellar motor, triggering a signaling cascade that enhances adhesion. This mechanism reveals how bacteria like Caulobacter crescentus attach to surfaces.
Area of Science:
- Microbiology
- Cellular Biology
- Biophysics
Background:
- Bacteria exhibit surface colonization and virulence upon encountering surfaces.
- Mechanisms of bacterial mechanosensation and signal transduction are not fully understood.
Purpose of the Study:
- To elucidate the tactile sensing cascade in Caulobacter crescentus.
- To identify the role of the flagellar motor in bacterial surface sensing.
Main Methods:
- Investigated surface-induced signaling in Caulobacter crescentus.
- Analyzed the function of the flagellar motor, DgcB, and HfsJ in mechanosensation.
- Compared wild-type and mutant strains lacking flagellar structures.
Main Results:
- Surface contact triggers flagellar motor interference, activating DgcB to produce cyclic diguanylate.
- Cyclic diguanylate allosterically activates HfsJ, leading to polysaccharide adhesin synthesis and surface anchoring.
- Mutants lacking external flagellar structures showed hypersensitivity to mechanical stimuli.
Conclusions:
- The bacterial flagellar motor functions as a novel tetherless mechanosensor.
- This sensing cascade enables rapid bacterial surface adaptation and adhesion.
- Findings provide insights into bacterial surface interactions and mechanobiology.
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