8GRA

Structure of Type VI secretion system cargo delivery vehicle Hcp-VgrG-PAAR

これはPDB形式変換不可エントリーです。

8GRA の概要

• エントリーDOI: 10.2210/pdb8gra/pdb
• EMDBエントリー: 34087
• 分子名称: Type VI secretion system spike protein Paar, Bacterodales T6SS protein TssD (Hcp), Type VI secretion system spike protein VgrG (3 entities in total)
• 機能のキーワード: type vi secretion system, vgrg, hcp5, paar, transport protein
• 由来する生物種: Bacteroides fragilis; 詳細
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 362114.95

構造登録者

Wen, Y.,He, W.,Zhu, L. (登録日: 2022-09-01, 公開日: 2023-07-12, 最終更新日: 2025-06-25)

主引用文献

He, W.,Wu, K.,Ouyang, Z.,Bai, Y.,Luo, W.,Wu, D.,An, H.,Guo, Y.,Jiao, M.,Qin, Q.,Zhang, J.,Wu, Y.,She, J.,Hwang, P.M.,Zheng, F.,Zhu, L.,Wen, Y.
Structure and assembly of type VI secretion system cargo delivery vehicle.
Cell Rep, 42:112781-112781, 2023

PubMed Abstract: Type VI secretion system is widely used in Gram-negative bacteria for injecting toxic effectors into neighboring prokaryotic or eukaryotic cells. Various effectors can be loaded onto the T6SS delivery tube via its core components: Hcp, VgrG, or PAAR. Here, we report 2.8-Å resolution cryo-EM structure of intact T6SS Hcp5-VgrG-PAAR cargo delivery system and crystal structure of unbound Hcp5 from B. fragilis NCTC 9343. Loading of Hcp5 hexameric ring onto VgrG causes expansion of its inner cavity and external surface, explaining how structural changes could be propagated to regulate co-polymerization and surrounding contractile sheath. High-affinity binding between Hcp and VgrG causes entropically unfavorable structuring of long loops. Furthermore, interactions between VgrG trimer and Hcp hexamer are asymmetric, with three of the six Hcp monomers exhibiting a major loop flip. Our study provides insights into the assembly, loading, and firing of T6SS nanomachine that contributes to bacterial inter-species competition and host interactions.

PubMed: 37421630
DOI: 10.1016/j.celrep.2023.112781

実験手法

ELECTRON MICROSCOPY (2.8 Å)