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Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
Published on: December 31, 2019
Protein translocation across the bacterial cytoplasmic membrane
Arnold J M Driessen1, Nico Nouwen
1Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and the Zernike Institute for Advanced Materials, University of Groningen, Haren, The Netherlands. a.j.m.driessen@rug.nl
Annual Review of Biochemistry
|December 15, 2007
Summary
Bacterial cell envelope proteins are targeted to the Sec translocase for translocation across the membrane. This review details the Sec translocase mechanism, structure, and current research questions.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Approximately 25-30% of bacterial proteins are destined for the cell envelope or extracellular space.
- These proteins are synthesized in the cytosol and targeted for secretion via specific pathways.
Purpose of the Study:
- To review the current understanding of the Sec translocase mechanism and structure.
- To highlight unresolved questions and active areas of research concerning protein translocation in bacteria.
Main Methods:
- This review synthesizes existing knowledge from published research.
- It focuses on the structural and mechanistic aspects of the Sec translocase complex.
Main Results:
- The Sec translocase, comprising SecYEG and SecA, mediates protein translocation and membrane protein insertion.
- Protein targeting involves signal recognition particle (SRP) or SecB chaperones.
- Translocation is powered by ATP and proton motive force (PMF).
Conclusions:
- The Sec translocase is a critical complex for bacterial protein export.
- Further research is needed to fully elucidate its intricate mechanisms and structural dynamics.
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