8BNZ

BAM-EspP complex structure with BamA-G431C/EspP-N1293C mutations in nanodisc

Summary for 8BNZ

• Entry DOI: 10.2210/pdb8bnz/pdb
• EMDB information: 16137
• Descriptor: Outer membrane protein assembly factor BamA, Outer membrane protein assembly factor BamB, Outer membrane protein assembly factor BamC, ... (6 entities in total)
• Functional Keywords: bam, bamabcde, espp, gram-negative bacteria, outer membrane protein, outer membrane barrel, bama, bamb, bamc, bamd, bame, membrane protein, outer membrane protein insertion and release, transport protein
• Biological source: Escherichia coli K-12; More
• Total number of polymer chains: 6
• Total formula weight: 249600.12

Authors

Shen, C.,Chang, S.,Luo, Q.,Zhang, Z.,Xie, T.,Luo, B.,Lu, G.,Zhu, X.,Wei, X.,Dong, C.,Zhou, R.,Zhang, X.,Tang, X.,Dong, H. (deposition date: 2022-11-14, release date: 2023-04-26, Last modification date: 2024-10-23)

Primary citation

Shen, C.,Chang, S.,Luo, Q.,Chan, K.C.,Zhang, Z.,Luo, B.,Xie, T.,Lu, G.,Zhu, X.,Wei, X.,Dong, C.,Zhou, R.,Zhang, X.,Tang, X.,Dong, H.
Structural basis of BAM-mediated outer membrane beta-barrel protein assembly.
Nature, 617:185-193, 2023

PubMed Abstract: The outer membrane structure is common in Gram-negative bacteria, mitochondria and chloroplasts, and contains outer membrane β-barrel proteins (OMPs) that are essential interchange portals of materials. All known OMPs share the antiparallel β-strand topology, implicating a common evolutionary origin and conserved folding mechanism. Models have been proposed for bacterial β-barrel assembly machinery (BAM) to initiate OMP folding; however, mechanisms by which BAM proceeds to complete OMP assembly remain unclear. Here we report intermediate structures of BAM assembling an OMP substrate, EspP, demonstrating sequential conformational dynamics of BAM during the late stages of OMP assembly, which is further supported by molecular dynamics simulations. Mutagenic in vitro and in vivo assembly assays reveal functional residues of BamA and EspP for barrel hybridization, closure and release. Our work provides novel insights into the common mechanism of OMP assembly.

PubMed: 37100902
DOI: 10.1038/s41586-023-05988-8

Experimental method

ELECTRON MICROSCOPY (3.5 Å)