Pilus retraction powers bacterial twitching motility

@article{Merz2000PilusRP,
  title={Pilus retraction powers bacterial twitching motility},
  author={Alexey J. Merz and Magdalene Maggie So and Michael P. Sheetz},
  journal={Nature},
  year={2000},
  volume={407},
  pages={98-102}
}
Twitching and social gliding motility allow many Gram negative bacteria to crawl along surfaces, and are implicated in a wide range of biological functions. Type IV pili (Tfp) are required for twitching and social gliding, but the mechanism by which these filaments promote motility has remained enigmatic. Here we use laser tweezers to show that Tfp forcefully retract. Neisseria gonorrhoeae cells that produce Tfp actively crawl on a glass surface and form adherent microcolonies. When laser… 

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TLDR
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TLDR
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TLDR
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TLDR
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Direct observation of extension and retraction of type IV pili

  • J. SkerkerH. Berg
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2001
TLDR
Type IV pili are linear actuators that extend, attach at their distal tips, exert substantial force, and retract, and are required for twitching motility in Pseudomonas aeruginosa and Neisseria gonorrhoeae.

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TLDR
This review focuses on recent discoveries relating to the assembly and function of T4P in generation of twitching motility, involving retractable pili belonging to the F‐like subgroup of the type IV secretion family.

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TLDR
The results demonstrate that sensory systems, whose input often remains elusive, can sense mechanical signals to actively steer motility and establish a signaling principle shared with higher-order organisms, identifying a conserved strategy to transduce spatially resolved signals.

Type IV pili and twitching motility.

  • J. Mattick
  • Biology
    Annual review of microbiology
  • 2002
TLDR
Twitching motility is a flagella-independent form of bacterial translocation over moist surfaces that is important in host colonization by a wide range of plant and animal pathogens, as well as in the formation of biofilms and fruiting bodies.

PilT2 enhances the speed of gonococcal type IV pilus retraction and of twitching motility

TLDR
The speed of single T4P retraction was reduced by a factor of ≈ 2 in a pilT2 deletion strain, whereas pilU deletion showed a minor effect and the maximum force and the probability for switching from retraction to elongation under application of high force were not significantly affected.
...

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