4RFS

Structure of a pantothenate energy coupling factor transporter

4RFS の概要

• エントリーDOI: 10.2210/pdb4rfs/pdb
• 分子名称: Energy-coupling factor transporter ATP-binding protein EcfA2, Energy-coupling factor transporter ATP-binding protein EcfA1, Substrate binding pritein S, ... (4 entities in total)
• 機能のキーワード: transporter, ecf, hydrolase, transport protein
• 由来する生物種: Lactobacillus brevis; 詳細
• 細胞内の位置: Cell membrane ; Peripheral membrane protein : Q03PY6 Q03PY5; Cell membrane ; Multi-pass membrane protein : Q03PY7
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 116876.34

構造登録者

Zhang, M.,Bao, Z.,Zhao, Q.,Guo, H.,Xu, K.,Zhang, P. (登録日: 2014-09-27, 公開日: 2014-12-24, 最終更新日: 2024-02-28)

主引用文献

Zhang, M.,Bao, Z.,Zhao, Q.,Guo, H.,Xu, K.,Wang, C.,Zhang, P.
Structure of a pantothenate transporter and implications for ECF module sharing and energy coupling of group II ECF transporters.
Proc.Natl.Acad.Sci.USA, 111:18560-18565, 2014

PubMed Abstract: Energy-coupling factor (ECF) transporters are a unique group of ATP-binding cassette (ABC) transporters responsible for micronutrient uptake from the environment. Each ECF transporter is composed of an S component (or EcfS protein) and T/A/A' components (or EcfT/A/A' proteins; ECF module). Among the group II ECF transporters, several EcfS proteins share one ECF module; however, the underlying mechanism remains unknown. Here we report the structure of a group II ECF transporter-pantothenate transporter from Lactobacillus brevis (LbECF-PanT), which shares the ECF module with the folate and hydroxymethylpyrimidine transporters (LbECF-FolT and LbECF-HmpT). Structural and mutational analyses revealed the residues constituting the pantothenate-binding pocket. We found that although the three EcfS proteins PanT, FolT, and HmpT are dissimilar in sequence, they share a common surface area composed of the transmembrane helices 1/2/6 (SM1/2/6) to interact with the coupling helices 2/3 (CH2/3) of the same EcfT. CH2 interacts mainly with SM1 via hydrophobic interactions, which may modulate the sliding movement of EcfS. CH3 binds to a hydrophobic surface groove formed by SM1, SM2, and SM6, which may transmit the conformational changes from EcfA/A' to EcfS. We also found that the residues at the intermolecular surfaces in LbECF-PanT are essential for transporter activity, and that these residues may mediate intermolecular conformational transmission and/or affect transporter complex stability. In addition, we found that the structure of EcfT is conformationally dynamic, which supports its function as a scaffold to mediate the interaction of the ECF module with various EcfS proteins to form different transporter complexes.

PubMed: 25512487
DOI: 10.1073/pnas.1412246112

実験手法

X-RAY DIFFRACTION (3.232 Å)