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Structural overview of the bacterial injectisome
Liam J Worrall1, Emilie Lameignere, Natalie C J Strynadka
1Department of Biochemistry and Molecular Biology, University of British Columbia, Life Sciences Centre, 2350 Health Sciences Mall Vancouver, British Columbia, Canada.
Current Opinion in Microbiology
|November 30, 2010
Summary
The bacterial injectisome, a virulence protein delivery system, has seen recent structural advances. This review details its components and assembly into a functional type III secretion system (T3SS).
Area of Science:
- Microbiology
- Structural Biology
- Molecular Biology
Background:
- Pathogenic Gram-negative bacteria use the injectisome for virulence protein delivery.
- The injectisome is a complex nanomachine composed of over 20 proteins.
- It forms a conduit from the bacterial to the host cell cytoplasm.
Purpose of the Study:
- To review the current understanding of the bacterial injectisome's structure.
- To focus on the molecular structures of individual injectisome components.
- To explain how these components assemble into a functional type III secretion system (T3SS).
Main Methods:
- X-ray crystallography
- Nuclear Magnetic Resonance (NMR) spectroscopy
- Electron Microscopy (EM)
Main Results:
- Significant progress has been made in elucidating the injectisome's structure.
- Detailed molecular structures of individual protein components are becoming available.
- Understanding of the assembly process is advancing.
Conclusions:
- The injectisome's structure is increasingly well-defined.
- Knowledge of component structures aids in understanding T3SS function.
- This review consolidates current structural insights into the injectisome.
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