3DIN

Crystal structure of the protein-translocation complex formed by the SecY channel and the SecA ATPase

3DIN の概要

• エントリーDOI: 10.2210/pdb3din/pdb
• 分子名称: Protein translocase subunit secA, Preprotein translocase subunit SecY, Preprotein translocase subunit secE, ... (7 entities in total)
• 機能のキーワード: protein translocation, membrane protein, atpase, atp-binding, inner membrane, nucleotide-binding, protein transport, transport, transmembrane
• 由来する生物種: Thermotoga maritima MSB8; 詳細
• 細胞内の位置: Cell inner membrane ; Peripheral membrane protein ; Cytoplasmic side : Q9X1R4; Cell inner membrane; Multi-pass membrane protein: Q9X1I9; Cell inner membrane; Single-pass membrane protein: P35874
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 329908.03

構造登録者

Zimmer, J.,Nam, Y.,Rapoport, T.A. (登録日: 2008-06-20, 公開日: 2008-10-07, 最終更新日: 2023-08-30)

主引用文献

Zimmer, J.,Nam, Y.,Rapoport, T.A.
Structure of a complex of the ATPase SecA and the protein-translocation channel.
Nature, 455:936-943, 2008

PubMed Abstract: Most proteins are secreted from bacteria by the interaction of the cytoplasmic SecA ATPase with a membrane channel, formed by the heterotrimeric SecY complex. Here we report the crystal structure of SecA bound to the SecY complex, with a maximum resolution of 4.5 ångström (A), obtained for components from Thermotoga maritima. One copy of SecA in an intermediate state of ATP hydrolysis is bound to one molecule of the SecY complex. Both partners undergo important conformational changes on interaction. The polypeptide-cross-linking domain of SecA makes a large conformational change that could capture the translocation substrate in a 'clamp'. Polypeptide movement through the SecY channel could be achieved by the motion of a 'two-helix finger' of SecA inside the cytoplasmic funnel of SecY, and by the coordinated tightening and widening of SecA's clamp above the SecY pore. SecA binding generates a 'window' at the lateral gate of the SecY channel and it displaces the plug domain, preparing the channel for signal sequence binding and channel opening.

PubMed: 18923516
DOI: 10.1038/nature07335

実験手法

X-RAY DIFFRACTION (4.5 Å)