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Updated: Jan 28, 2026
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Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
Published on: July 19, 2016
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The Dynamic Structures of the Type IV Pilus.
Matthew McCallum1,2, Lori L Burrows3, P Lynne Howell1,2
1Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.
Microbiology Spectrum
|March 3, 2019
Summary
Type IV pilus (T4P)-like systems are vital prokaryotic machines. Recent structural studies reveal how the type IVa pilus (T4aP) machinery assembles and functions, offering insights into diverse cellular processes.
Area of Science:
- Microbiology
- Structural Biology
- Molecular Biology
Background:
- Type IV pilus (T4P)-like systems are widespread in prokaryotes.
- These systems perform diverse functions including adhesion, motility, and secretion.
- The type IVa pilus (T4aP) is a versatile system, excluding swimming motility.
Purpose of the Study:
- To review the structure and function of the type IVa pilus (T4aP).
- To highlight recent advancements in understanding T4aP machinery assembly and function.
- To establish T4aP as a model for studying T4P-like systems.
Main Methods:
- Review of recent structural analyses of T4aP machinery.
- Synthesis of existing literature on T4P-like systems.
- Comparative analysis of T4aP functions with other T4P-like systems.
Main Results:
- Structural analyses have significantly advanced the understanding of T4aP assembly and function.
- T4aP machinery is implicated in adhesion, natural competence, phage adsorption, protein secretion, surface sensing, and twitching motility.
- The T4aP serves as an excellent model for comprehending the broader family of T4P-like systems.
Conclusions:
- The structure of T4aP machinery is key to its diverse functions.
- Understanding T4aP provides a framework for studying related prokaryotic systems.
- Continued structural and functional studies of T4aP will yield further insights into prokaryotic biology.
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