3UDC

Crystal structure of a membrane protein

3UDC の概要

• エントリーDOI: 10.2210/pdb3udc/pdb
• 関連するPDBエントリー: 3T9N
• 分子名称: Small-conductance mechanosensitive channel, C-terminal peptide from Small-conductance mechanosensitive channel (1 entity in total)
• 機能のキーワード: membrane protein, channel, mechanosensitive
• 由来する生物種: Thermoanaerobacter tengcongensis; 詳細
• 細胞内の位置: Cell inner membrane ; Multi-pass membrane protein : P0C0S1
• タンパク質・核酸の鎖数: 7
• 化学式量合計: 227235.26

構造登録者

Li, W.,Ge, J.,Yang, M. (登録日: 2011-10-28, 公開日: 2012-10-31, 最終更新日: 2023-11-01)

主引用文献

Zhang, X.,Wang, J.,Feng, Y.,Ge, J.,Li, W.,Sun, W.,Iscla, I.,Yu, J.,Blount, P.,Li, Y.,Yang, M.
Structure and molecular mechanism of an anion-selective mechanosensitive channel of small conductance
Proc.Natl.Acad.Sci.USA, 109:18180-18185, 2012

PubMed Abstract: Mechanosensitive (MS) channels are universal cellular membrane pores. Bacterial MS channels, as typified by MS channel of small conductance (MscS) from Escherichia coli (EcMscS), release osmolytes under hypoosmotic conditions. MS channels are known to be ion selective to different extents, but the underlying mechanism remains poorly understood. Here we identify an anion-selective MscS channel from Thermoanaerobacter tengcongensis (TtMscS). The structure of TtMscS closely resembles that of EcMscS, but it lacks the large cytoplasmic equatorial portals found in EcMscS. In contrast, the cytoplasmic pore formed by the C-terminal β-barrel of TtMscS is larger than that of EcMscS and has a strikingly different pattern of electrostatic surface potential. Swapping the β-barrel region between TtMscS and EcMscS partially switches the ion selectivity. Our study defines the role of the β-barrel in the ion selection of an anion-selective MscS channel and provides a structural basis for understanding the ion selectivity of MscS channels.

PubMed: 23074248
DOI: 10.1073/pnas.1207977109

実験手法

X-RAY DIFFRACTION (3.355 Å)