7TT4

BamABCDE bound to substrate EspP class 6

7TT4 の概要

• エントリーDOI: 10.2210/pdb7tt4/pdb
• 関連するPDBエントリー: 7TSZ 7TT0 7TT1 7TT2 7TT3 7TT4 7TT5 7TT6 7TT7
• EMDBエントリー: 26105 26106 26107 26108 26109 26110 26111 26112 26113
• 分子名称: 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)
• 機能のキーワード: membrane protein folding, membrane dynamics, outer membrane protein, bam, beta-barrel, membrane protein
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 283672.07

構造登録者

Doyle, M.T.,Jimah, J.R.,Dowdy, T.,Ohlemacher, S.I.,Larion, M.,Hinshaw, J.E.,Bernstein, H.D. (登録日: 2022-01-31, 公開日: 2022-03-30, 最終更新日: 2025-05-14)

主引用文献

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

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: 35294859
DOI: 10.1016/j.cell.2022.02.016

実験手法

ELECTRON MICROSCOPY (4.2 Å)