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Assembly and Subcellular Localization of Bacterial Type VI Secretion Systems
Jing Wang1, Maj Brodmann1, Marek Basler1
1Biozentrum, University of Basel, CH 4056 Basel, Switzerland;
Annual Review of Microbiology
|June 22, 2019
Summary
Bacteria use the type VI secretion system (T6SS) to inject toxins into target cells. This dynamic system
Area of Science:
- Microbiology
- Molecular Biology
- Cell Biology
Background:
- Bacteria secrete molecules to interact with their environment and other cells.
- Protein secretion systems are crucial for bacterial survival and function.
- The type VI secretion system (T6SS) is a large, dynamic protein complex used by Gram-negative bacteria.
Purpose of the Study:
- To describe the structure and function of the type VI secretion system (T6SS).
- To highlight recent advances in understanding T6SS mechanisms.
- To explain how bacteria regulate T6SS localization for efficient toxin delivery.
Main Methods:
- Structural biology techniques to visualize T6SS components.
- Live-cell imaging to observe T6SS dynamics in real-time.
- Analysis of T6SS assembly, contraction, and toxin translocation.
Main Results:
- The T6SS functions as a contractile machine, propelling toxins into target cells.
- T6SS structure involves a contractile sheath, rigid tube, baseplate, and membrane complex.
- Bacteria actively reposition the T6SS to enhance toxin delivery efficiency.
Conclusions:
- The T6SS is a sophisticated nanomachine for bacterial intercellular communication and warfare.
- Understanding T6SS structure and regulation provides insights into bacterial pathogenesis.
- Dynamic subcellular localization is key to maximizing T6SS effectiveness.
Keywords:
bacterial secretion systemscontractile nanomachinessensing and signaling cascadessubcellular localizationMore Related Videos
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