5X3X

2.8A resolution structure of a cobalt energy-coupling factor transporter-CbiMQO

5X3X の概要

• エントリーDOI: 10.2210/pdb5x3x/pdb
• 関連するPDBエントリー: 5X40 5X41
• 分子名称: Cobalt ABC transporter ATP-binding protein, Cobalt transport protein CbiM, Uncharacterized protein CbiQ, ... (4 entities in total)
• 機能のキーワード: complex, ecf transporter, transport protein
• 由来する生物種: Rhodobacter capsulatus; 詳細
• 細胞内の位置: Cell membrane ; Multi-pass membrane protein : A0A0Q0R232
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 214751.16

構造登録者

Bao, Z.,Qi, X.,Wang, J.,Zhang, P. (登録日: 2017-02-09, 公開日: 2017-04-05, 最終更新日: 2024-03-27)

主引用文献

Bao, Z.,Qi, X.,Hong, S.,Xu, K.,He, F.,Zhang, M.,Chen, J.,Chao, D.,Zhao, W.,Li, D.,Wang, J.,Zhang, P.
Structure and mechanism of a group-I cobalt energy coupling factor transporter
Cell Res., 27:675-687, 2017

PubMed Abstract: Energy-coupling factor (ECF) transporters are a large family of ATP-binding cassette transporters recently identified in microorganisms. Responsible for micronutrient uptake from the environment, ECF transporters are modular transporters composed of a membrane substrate-binding component EcfS and an ECF module consisting of an integral membrane scaffold component EcfT and two cytoplasmic ATP binding/hydrolysis components EcfA/A'. ECF transporters are classified into groups I and II. Currently, the molecular understanding of group-I ECF transporters is very limited, partly due to a lack of transporter complex structural information. Here, we present structures and structure-based analyses of the group-I cobalt ECF transporter CbiMNQO, whose constituting subunits CbiM/CbiN, CbiQ, and CbiO correspond to the EcfS, EcfT, and EcfA components of group-II ECF transporters, respectively. Through reconstitution of different CbiMNQO subunits and determination of related ATPase and transporter activities, the substrate-binding subunit CbiM was found to stimulate CbiQO's basal ATPase activity. The structure of CbiMQO complex was determined in its inward-open conformation and that of CbiO in β, γ-methyleneadenosine 5'-triphosphate-bound closed conformation. Structure-based analyses revealed interactions between different components, substrate-gating function of the L1 loop of CbiM, and conformational changes of CbiO induced by ATP binding and product release within the CbiMNQO transporter complex. These findings enabled us to propose a working model of the CbiMNQO transporter, in which the transport process requires the rotation or toppling of both CbiQ and CbiM, and CbiN might function in coupling conformational changes between CbiQ and CbiM.

PubMed: 28322252
DOI: 10.1038/cr.2017.38

実験手法

X-RAY DIFFRACTION (2.788 Å)