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The Sec System: Protein Export in Escherichia coli
Jennine M Crane1, Linda L Randall1
1Department of Biochemistry, University of Missouri, Columbia, MO 65201.
Ecosal Plus
|November 23, 2017
Summary
The general secretory (Sec) system in Escherichia coli exports proteins across the cell membrane. This review covers the Sec system
Area of Science:
- Molecular Biology
- Cell Biology
- Microbiology
Background:
- Proteins destined for the periplasm or outer membrane of Escherichia coli are translocated from the cytoplasm.
- The general secretory (Sec) system is the primary pathway for this protein export.
- This process is crucial for bacterial cell envelope biogenesis and function.
Purpose of the Study:
- To provide a comprehensive review of the Escherichia coli Sec system.
- To summarize key findings from biochemical, genetic, and structural studies up to early 2016.
- To highlight the dynamic and complex nature of protein export.
Main Methods:
- Review of existing literature, including biochemical, genetic, and structural data.
- Analysis of protein-lipid and protein-protein interactions involved in secretion.
- Integration of in vivo data regarding energy requirements (ATP hydrolysis and proton motive force).
Main Results:
- The Sec system involves intricate interactions between cytoplasmic and membrane proteins (peripheral and integral) and lipids.
- Both ATP hydrolysis and proton motive force are essential for in vivo protein translocation.
- The review consolidates a significant body of knowledge on the Sec system's mechanisms.
Conclusions:
- The Sec system is a complex machinery essential for bacterial protein export.
- Understanding these export pathways is vital for comprehending bacterial physiology and developing novel antimicrobial strategies.
- Continued research integrating various data types will further elucidate the Sec system's intricacies.
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