The structure of the beta-barrel assembly machinery complex.
Bakelar, J., Buchanan, S.K., Noinaj, N.(2016) Science 351: 180-186
- PubMed: 26744406 
- DOI: https://doi.org/10.1126/science.aad3460
- Primary Citation of Related Structures:  
5EKQ - PubMed Abstract: 
β-Barrel outer membrane proteins (OMPs) are found in the outer membranes of Gram-negative bacteria and are essential for nutrient import, signaling, and adhesion. A 200-kilodalton five-component complex called the β-barrel assembly machinery (BAM) complex has been implicated in the biogenesis of OMPs. We report the structure of the BAM complex from Escherichia coli, revealing that binding of BamCDE modulates the conformation of BamA, the central component, which may serve to regulate the BAM complex. The periplasmic domain of BamA was in a closed state that prevents access to the barrel lumen, which indicates substrate OMPs may not be threaded through the barrel during biogenesis. Further, conformational shifts in the barrel domain lead to opening of the exit pore and rearrangement at the lateral gate.
Organizational Affiliation: 
Markey Center for Structural Biology, Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.