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Updated: Aug 1, 2026
11:33
Monitoring the Assembly of a Secreted Bacterial Virulence Factor Using Site-specific Crosslinking
Published on: December 17, 2013
Pilus biogenesis via the chaperone/usher pathway: an integration of structure and function
1Department of Molecular Microbiology, Washington University, St. Louis, Missouri, 63110, USA.
Journal of Structural Biology
|March 2, 1999
Summary
Pathogenic bacteria use P pili, hair-like structures, to attach to host tissues, causing infections. Studying P pilus assembly reveals common mechanisms in bacterial disease development.
Area of Science:
- Microbiology
- Structural Biology
- Molecular Biology
Background:
- Microbial attachment to host tissues is crucial for bacterial pathogenesis.
- Adhesins, assembled into pili, mediate this attachment on bacterial surfaces.
- P pili from uropathogenic Escherichia coli are a model for studying these processes.
Purpose of the Study:
- To investigate the structure-function relationships of P pili.
- To elucidate the common themes in virulence factor assembly via the chaperone/usher pathway.
- To understand the molecular basis of bacterial adhesion and pathogenesis.
Main Methods:
- X-ray crystallography
- Protein chemistry
- High-resolution electron microscopy
- Cell biology
- Genetic systems
Main Results:
- P pili are assembled through a conserved chaperone/usher pathway.
- This pathway is utilized by over 30 adhesive organelles in Gram-negative pathogens.
- Detailed structural insights into pilus biogenesis were obtained.
Conclusions:
- P pilus biogenesis serves as a model for understanding protein folding, secretion, and assembly of bacterial virulence factors.
- The study provides structural insights into the function and consequences of microbial attachment.
- Understanding these mechanisms is key to developing strategies against bacterial infections.
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