5A43

Crystal structure of a dual topology fluoride ion channel.

5A43 の概要

• エントリーDOI: 10.2210/pdb5a43/pdb
• 関連するPDBエントリー: 5A40 5A41
• 分子名称: PUTATIVE FLUORIDE ION TRANSPORTER CRCB, MONOBODIES, FLUORIDE ION, ... (6 entities in total)
• 機能のキーワード: transport protein, fluoride ion channel, fluc, ec2
• 由来する生物種: ESCHERICHIA COLI S88; 詳細
• 細胞内の位置: Cell inner membrane ; Multi-pass membrane protein : B7LI20
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 49965.43

構造登録者

Stockbridge, R.B.,Kolmakova-Partensky, L.,Shane, T.,Koide, A.,Koide, S.,Miller, C.,Newstead, S. (登録日: 2015-06-04, 公開日: 2015-09-02, 最終更新日: 2024-11-13)

主引用文献

Stockbridge, R.B.,Kolmakova-Partensky, L.,Shane, T.,Koide, A.,Koide, S.,Miller, C.,Newstead, S.
Crystal Structures of a Double-Barrelled Fluoride Ion Channel.
Nature, 525:548-, 2015

PubMed Abstract: To contend with hazards posed by environmental fluoride, microorganisms export this anion through F(-)-specific ion channels of the Fluc family. Since the recent discovery of Fluc channels, numerous idiosyncratic features of these proteins have been unearthed, including strong selectivity for F(-) over Cl(-) and dual-topology dimeric assembly. To understand the chemical basis for F(-) permeation and how the antiparallel subunits convene to form a F(-)-selective pore, here we solve the crystal structures of two bacterial Fluc homologues in complex with three different monobody inhibitors, with and without F(-) present, to a maximum resolution of 2.1 Å. The structures reveal a surprising 'double-barrelled' channel architecture in which two F(-) ion pathways span the membrane, and the dual-topology arrangement includes a centrally coordinated cation, most likely Na(+). F(-) selectivity is proposed to arise from the very narrow pores and an unusual anion coordination that exploits the quadrupolar edges of conserved phenylalanine rings.

PubMed: 26344196
DOI: 10.1038/NATURE14981

実験手法

X-RAY DIFFRACTION (2.58 Å)