Bacteria Swim by Rotating their Flagellar Filaments

@article{Berg1973BacteriaSB,
  title={Bacteria Swim by Rotating their Flagellar Filaments},
  author={Howard C. Berg and Robert A. Anderson},
  journal={Nature},
  year={1973},
  volume={245},
  pages={380-382}
}
IT is widely agreed that bacteria swim by moving their flagella, but how this motion is generated remains obscure1,2. A flagellum has a helical filament, a proximal hook, and components at its base associated with the cell wall and the cytoplasmic membrane. If there are several flagella per cell, the filaments tend to form bundles and to move in unison. When viewed by high-speed cinematography, the bundles show a screw-like motion. It is commonly believed that each filament propagates a helical… 
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  • Biology
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  • 1991
TLDR
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TLDR
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TLDR
A model for the electromechanical coupling between ion flow and flagellar rotation is proposed and it is shown that this coupling is driven by the translocation of ions down an electrochemical gradient.
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TLDR
It is proposed that gliding motility in bacteria is based on rotary assemblies located in the cell envelope and that these assemblies may be analogous to basal regions of bacterial flagella, and the active movement of latex spheres along surfaces of gliding bacteria appears to depend on mechanisms responsible for motility.
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TLDR
Regardless of the type of motility machinery that is employed, most motile microorganisms use complex sensory systems to control their movements in response to stimuli, which allows them to migrate to optimal environments.
Flagellar Hook Flexibility Is Essential for Bundle Formation in Swimming Escherichia coli Cells
TLDR
Genetically modified the hook so that it could be stiffened by binding streptavidin to biotinylated monomers, impeding their motion relative to each other resulted in atypical swimming behavior as a consequence of disrupted bundle formation, in agreement with the universal joint model.
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TLDR
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