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Updated: Jul 20, 2026
06:27
Analysis of β-Amyloid-induced Abnormalities on Fibrin Clot Structure by Spectroscopy and Scanning Electron Microscopy
Published on: November 30, 2018
The solution structure of the invasive tip complex from Afa/Dr fibrils
Ernesto Cota1, Celine Jones, Peter Simpson
1Division of Molecular Biosciences, Biochemistry Building, Imperial College London, South Kensington, London SW7 2AZ, UK.
Molecular Microbiology
|September 13, 2006
Summary
Afa/Dr adhesins from pathogenic Escherichia coli are key to chronic diarrhea and urinary tract infections. New structural insights reveal how these bacterial adhesins recognize host cells for invasion.
Area of Science:
- Microbiology
- Structural Biology
- Infectious Diseases
Background:
- Afa/Dr adhesins are virulence factors in pathogenic Escherichia coli.
- These adhesins are associated with chronic diarrheal and recurrent urinary tract infections, including cystitis in children and pyelonephritis in pregnant women.
- Afa/Dr adhesins function as capped surface fibrils mediating host cell recognition and bacterial internalization.
Purpose of the Study:
- To elucidate the architecture of the Afa/Dr adhesin fibrillar cap.
- To identify the mechanism of synergistic integrin recognition mediated by the AfaDE complex.
Main Methods:
- Three-dimensional structure determination of the minimal invasive complex (AfaDE).
- Biochemical assays.
- Cellular assays.
Main Results:
- Detailed architecture of the Afa/Dr adhesin fibrillar cap was revealed.
- A novel mode of synergistic integrin recognition was identified.
- Structural and functional insights into bacterial adhesion and invasion mechanisms.
Conclusions:
- The study provides a structural basis for Afa/Dr adhesin function.
- Understanding these mechanisms can inform strategies against E. coli infections.
- Novel insights into host-pathogen interactions and bacterial virulence factors.
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