5WQ8

CryoEM structure of type II secretion system secretin GspD in Vibrio cholerae

5WQ8 の概要

• エントリーDOI: 10.2210/pdb5wq8/pdb
• 関連するPDBエントリー: 5WQ7 5WQ9
• EMDBエントリー: 6676
• 分子名称: Type II secretion system protein D (1 entity in total)
• 機能のキーワード: secretin, c15 symmetry, t2ss, protein transport
• 由来する生物種: Vibrio cholerae O1 biovar El Tor str. N16961
• タンパク質・核酸の鎖数: 15
• 化学式量合計: 1062946.17

構造登録者

Yan, Z.,Yin, M.,Li, X. (登録日: 2016-11-23, 公開日: 2016-12-28, 最終更新日: 2024-10-16)

主引用文献

Yan, Z.,Yin, M.,Xu, D.,Zhu, Y.,Li, X.
Structural insights into the secretin translocation channel in the type II secretion system
Nat. Struct. Mol. Biol., 24:177-183, 2017

PubMed Abstract: The secretin GspD of the type II secretion system (T2SS) forms a channel across the outer membrane in Gram-negative bacteria to transport substrates from the periplasm to the extracellular milieu. The lack of an atomic-resolution structure of the GspD channel hinders the investigation of substrate translocation mechanism of T2SS. Here we report cryo-EM structures of two GspD channels (∼1 MDa), from Escherichia coli K12 and Vibrio cholerae, at ∼3 Å resolution. The structures reveal a pentadecameric channel architecture, wherein three rings of GspD N domains form the periplasmic channel. The secretin domain constitutes a novel double β-barrel channel, with at least 60 β-strands in each barrel, and is stabilized by S domains. The outer membrane channel is sealed by β-strand-enriched gates. On the basis of the partially open state captured, we proposed a detailed gate-opening mechanism. Our structures provide a structural basis for understanding the secretin superfamily and the mechanism of substrate translocation in T2SS.

PubMed: 28067918
DOI: 10.1038/nsmb.3350

実験手法

ELECTRON MICROSCOPY (3.26 Å)