5EFR

Crystal Structure of a BamA-BamD fusion

Summary for 5EFR

• Entry DOI: 10.2210/pdb5efr/pdb
• Descriptor: BamA-BamD fusion Protein (2 entities in total)
• Functional Keywords: fusion, cell adhesion
• Biological source: Rhodothermus marinus; More
• Total number of polymer chains: 1
• Total formula weight: 51254.89

Authors

Bergal, H.T.,Hopkins, A.H.,Metzner, S.I.,Sousa, M.C. (deposition date: 2015-10-24, release date: 2016-01-27, Last modification date: 2023-09-27)

Primary citation

Bergal, H.T.,Hopkins, A.H.,Metzner, S.I.,Sousa, M.C.
The Structure of a BamA-BamD Fusion Illuminates the Architecture of the beta-Barrel Assembly Machine Core.
Structure, 24:243-251, 2016

PubMed Abstract: The β-barrel assembly machine (BAM) mediates folding and insertion of integral β-barrel outer membrane proteins (OMPs) in Gram-negative bacteria. Of the five BAM subunits, only BamA and BamD are essential for cell viability. Here we present the crystal structure of a fusion between BamA POTRA4-5 and BamD from Rhodothermus marinus. The POTRA5 domain binds BamD between its tetratricopeptide repeats 3 and 4. The interface structural elements are conserved in the Escherichia coli proteins, which allowed structure validation by mutagenesis and disulfide crosslinking in E. coli. Furthermore, the interface is consistent with previously reported mutations that impair BamA-BamD binding. The structure serves as a linchpin to generate a BAM model where POTRA domains and BamD form an elongated periplasmic ring adjacent to the membrane with a central cavity approximately 30 × 60 Å wide. We propose that nascent OMPs bind this periplasmic ring prior to insertion and folding by BAM.

PubMed: 26749448
DOI: 10.1016/j.str.2015.10.030

Experimental method

X-RAY DIFFRACTION (2 Å)