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Tractable Mammalian Cell Infections with Protozoan-primed Bacteria
Published on: April 2, 2013
Priming virulence factors for delivery into the host
C Erec Stebbins1, Jorge E Galán
1Laboratory of Structural Microbiology, The Rockefeller University, Box 52, 1230 York Avenue, New York, New York 10021, USA. stebbins@rockeffeler.edu
Nature Reviews. Molecular Cell Biology
|September 25, 2003
Summary
Bacterial chaperones help Gram-negative pathogens deliver toxins into host cells. These chaperones keep toxins in a state ready for unfolding and injection via the type III secretion system.
Area of Science:
- Microbiology
- Molecular Biology
- Structural Biology
Background:
- Gram-negative bacteria utilize type III secretion systems (T3SS) to deliver virulence factors into host cells.
- Specialized bacterial chaperones are essential for the efficient translocation of these virulence factors.
Approach:
- Recent structural studies investigated the role of bacterial chaperones in T3SS function.
- Analysis focused on the conformational state of virulence factors bound to chaperones.
Key Points:
- Bacterial chaperones bind to virulence factors, maintaining them in a partially unfolded, non-globular state.
- This specific conformation is crucial for priming the virulence factors for unfolding and translocation.
- The 'injectisome' acts as the translocon through which these factors are delivered.
Conclusions:
- Bacterial chaperones are key regulators of virulence factor delivery by T3SS.
- Structural insights reveal a mechanism for preparing effector proteins for host cell entry.
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