6WIM

CdiB from Escherichia coli

6WIM の概要

• エントリーDOI: 10.2210/pdb6wim/pdb
• 分子名称: Outer membrane transporter CdiB, DI(HYDROXYETHYL)ETHER, 1,2-ETHANEDIOL, ... (4 entities in total)
• 機能のキーワード: membrane protein, transport protein, tpsb, omp85, cdib
• 由来する生物種: Escherichia coli
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 60294.06

構造登録者

Guerin, J.,Botos, I.,Buchanan, S.K. (登録日: 2020-04-10, 公開日: 2020-11-04, 最終更新日: 2024-10-09)

主引用文献

Guerin, J.,Botos, I.,Zhang, Z.,Lundquist, K.,Gumbart, J.C.,Buchanan, S.K.
Structural insight into toxin secretion by contact dependent growth inhibition transporters.
Elife, 9:-, 2020

PubMed Abstract: Bacterial contact-dependent growth inhibition (CDI) systems use a type Vb secretion mechanism to export large CdiA toxins across the outer membrane by dedicated outer membrane transporters called CdiB. Here, we report the first crystal structures of two CdiB transporters from and . CdiB transporters adopt a TpsB fold, containing a 16-stranded transmembrane β-barrel connected to two periplasmic domains. The lumen of the CdiB pore is occluded by an N-terminal α-helix and the conserved extracellular loop 6; these two elements adopt different conformations in the structures. We identified a conserved DxxG motif located on strand β1 that connects loop 6 through different networks of interactions. Structural modifications of DxxG induce rearrangement of extracellular loops and alter interactions with the N-terminal α-helix, preparing the system for α-helix ejection. Using structural biology, functional assays, and molecular dynamics simulations, we show how the barrel pore is primed for CdiA toxin secretion.

PubMed: 33089781
DOI: 10.7554/eLife.58100

実験手法

X-RAY DIFFRACTION (2.6 Å)