7TT4
BamABCDE bound to substrate EspP class 6
Summary for 7TT4
Entry DOI | 10.2210/pdb7tt4/pdb |
Related | 7TSZ 7TT0 7TT1 7TT2 7TT3 7TT4 7TT5 7TT6 7TT7 |
EMDB information | 26105 26106 26107 26108 26109 26110 26111 26112 26113 |
Descriptor | Outer membrane protein assembly factor BamA, Maltose/maltodextrin-binding periplasmic protein,Serine protease EspP chimera, Outer membrane protein assembly factor BamD, ... (6 entities in total) |
Functional Keywords | membrane protein folding, membrane dynamics, outer membrane protein, bam, beta-barrel, membrane protein |
Biological source | Escherichia coli More |
Total number of polymer chains | 6 |
Total formula weight | 283672.07 |
Authors | Doyle, M.T.,Jimah, J.R.,Dowdy, T.,Ohlemacher, S.I.,Larion, M.,Hinshaw, J.E.,Bernstein, H.D. (deposition date: 2022-01-31, release date: 2022-03-30, Last modification date: 2024-10-23) |
Primary citation | Doyle, M.T.,Jimah, J.R.,Dowdy, T.,Ohlemacher, S.I.,Larion, M.,Hinshaw, J.E.,Bernstein, H.D. Cryo-EM structures reveal multiple stages of bacterial outer membrane protein folding. Cell, 185:1143-, 2022 Cited by PubMed Abstract: Transmembrane β barrel proteins are folded into the outer membrane (OM) of Gram-negative bacteria by the β barrel assembly machinery (BAM) via a poorly understood process that occurs without known external energy sources. Here, we used single-particle cryo-EM to visualize the folding dynamics of a model β barrel protein (EspP) by BAM. We found that BAM binds the highly conserved "β signal" motif of EspP to correctly orient β strands in the OM during folding. We also found that the folding of EspP proceeds via "hybrid-barrel" intermediates in which membrane integrated β sheets are attached to the essential BAM subunit, BamA. The structures show an unprecedented deflection of the membrane surrounding the EspP intermediates and suggest that β sheets progressively fold toward BamA to form a β barrel. Along with in vivo experiments that tracked β barrel folding while the OM tension was modified, our results support a model in which BAM harnesses OM elasticity to accelerate β barrel folding. PubMed: 35294859DOI: 10.1016/j.cell.2022.02.016 PDB entries with the same primary citation |
Experimental method | ELECTRON MICROSCOPY (4.2 Å) |
Structure validation
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