8CP7

Structure of the disulfide-locked substrate binding protein HiSiaP.

8CP7 の概要

• エントリーDOI: 10.2210/pdb8cp7/pdb
• 分子名称: Sialic acid-binding periplasmic protein SiaP, N-acetyl-beta-neuraminic acid, ZINC ION, ... (4 entities in total)
• 機能のキーワード: substrate binding protein, trap, sialic acid, sugar binding protein
• 由来する生物種: Haemophilus influenzae
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 35135.44

構造登録者

Kim, Y.,Peter, M.F.,Hagelueken, G. (登録日: 2023-03-02, 公開日: 2023-12-27, 最終更新日: 2024-10-16)

主引用文献

Peter, M.F.,Ruland, J.A.,Kim, Y.,Hendricks, P.,Schneberger, N.,Siebrasse, J.P.,Thomas, G.H.,Kubitscheck, U.,Hagelueken, G.
Conformational coupling of the sialic acid TRAP transporter HiSiaQM with its substrate binding protein HiSiaP.
Nat Commun, 15:217-217, 2024

PubMed Abstract: The tripartite ATP-independent periplasmic (TRAP) transporters use an extra cytoplasmic substrate binding protein (SBP) to transport a wide variety of substrates in bacteria and archaea. The SBP can adopt an open- or closed state depending on the presence of substrate. The two transmembrane domains of TRAP transporters form a monomeric elevator whose function is strictly dependent on the presence of a sodium ion gradient. Insights from experimental structures, structural predictions and molecular modeling have suggested a conformational coupling between the membrane elevator and the substrate binding protein. Here, we use a disulfide engineering approach to lock the TRAP transporter HiSiaPQM from Haemophilus influenzae in different conformational states. The SBP, HiSiaP, is locked in its substrate-bound form and the transmembrane elevator, HiSiaQM, is locked in either its assumed inward- or outward-facing states. We characterize the disulfide-locked constructs and use single-molecule total internal reflection fluorescence (TIRF) microscopy to study their interactions. Our experiments demonstrate that the SBP and the transmembrane elevator are indeed conformationally coupled, meaning that the open and closed state of the SBP recognize specific conformational states of the transporter and vice versa.

PubMed: 38191530
DOI: 10.1038/s41467-023-44327-3

実験手法

X-RAY DIFFRACTION (1.9 Å)