9MGG
beta-barrel assembly machine from Escherichia coli in a late state of substrate assembly
Summary for 9MGG
| Entry DOI | 10.2210/pdb9mgg/pdb |
| EMDB information | 48255 |
| Descriptor | Outer membrane protein assembly factor BamA, Outer membrane protein assembly factor BamC, Outer membrane protein assembly factor BamD, ... (6 entities in total) |
| Functional Keywords | beta-barrel assembly machine, outer membrane, folding intermediate, membrane protein |
| Biological source | Escherichia coli K-12 More |
| Total number of polymer chains | 6 |
| Total formula weight | 271424.23 |
| Authors | Thomson, B.D.,Kahne, D. (deposition date: 2024-12-10, release date: 2025-12-17, Last modification date: 2025-12-24) |
| Primary citation | Thomson, B.D.,Marquez, M.D.,Rawson, S.,Dos Santos, T.M.A.,Harrison, S.C.,Kahne, D. Structures of folding intermediates on BAM show diverse substrates fold by a uniform mechanism. Biorxiv, 2025 Cited by PubMed Abstract: The outer membranes of mitochondria, chloroplasts, and Gram-negative bacteria contain β-barrel membrane proteins that are assembled by conserved multi-subunit machines. In bacteria, the β-barrel assembly machine (BAM) folds over a hundred compositionally different substrates into barrels that vary greatly in size. Some larger barrels require globular proteins to plug the barrel lumen. How a single machine can assemble such different barrels is unknown. Here we report three structures representing progressively folded stages of a 16-stranded barrel engaged with BAM, as well as the structure of a late-stage folding intermediate of a 26-stranded substrate folding around its soluble lipoprotein plug on BAM. We find that BAM catalyzes folding of these substrates by a uniform mechanism in which BAM undergoes major distortions to accommodate the nascent barrel. PubMed: 41280068DOI: 10.1101/2025.10.16.682720 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.9 Å) |
Structure validation
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