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Updated: Jun 5, 2026
09:55
From Constructs to Crystals – Towards Structure Determination of β-barrel Outer Membrane Proteins
Published on: July 4, 2016
Structure and function of BamE within the outer membrane and the β-barrel assembly machine
Timothy J Knowles1, Douglas F Browning, Mark Jeeves
1School of Cancer Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
EMBO Reports
|January 8, 2011
Summary
The bacterial outer membrane protein assembly machine (Bam) component, BamE, is monomeric in the periplasm but dimerizes in the cytoplasm. This study reveals BamE
Area of Science:
- Microbiology
- Structural Biology
- Biochemistry
Background:
- Gram-negative bacteria outer membrane protein insertion relies on the essential β-barrel assembly machine (Bam).
- BamE is a core component of the Bam complex, crucial for its function.
Purpose of the Study:
- To elucidate the native structure and mechanism of BamE.
- To understand BamE's conformational changes and interactions within the Bam complex.
Main Methods:
- Native structural analysis of BamE.
- Mutagenesis studies to map binding determinants.
- Interaction studies to define functional roles.
Main Results:
- BamE exists as a monomer in the periplasm and adopts a dimeric form in the cytoplasm.
- BamE specifically binds to phosphatidylglycerol.
- Key determinants for Bam complex binding, outer membrane integrity, and cell viability were identified.
Conclusions:
- BamE undergoes conformational changes influencing its function in protein insertion.
- Phosphatidylglycerol binding and dimerization are critical for BamE's role in the Bam complex.
- This work clarifies BamE's mechanism and its contribution to outer membrane homeostasis.
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