4CZA

Structure of the sodium proton antiporter PaNhaP from Pyrococcus abyssii with bound thallium ion.

4CZA の概要

• エントリーDOI: 10.2210/pdb4cza/pdb
• 関連するPDBエントリー: 4CZ8 4CZ9 4CZB
• 分子名称: NA+/H+ ANTIPORTER, PUTATIVE, TRIS(HYDROXYETHYL)AMINOMETHANE, octyl beta-D-glucopyranoside, ... (7 entities in total)
• 機能のキーワード: membrane protein, transporter, exchanger, cpa
• 由来する生物種: PYROCOCCUS ABYSSI GE5
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 95056.74

構造登録者

Woehlert, D.,Kuhlbrandt, W.,Yildiz, O. (登録日: 2014-04-16, 公開日: 2014-12-17, 最終更新日: 2023-12-20)

主引用文献

Wohlert, D.,Kuhlbrandt, W.,Yildiz, O.
Structure and substrate ion binding in the sodium/proton antiporter PaNhaP.
Elife, 3:e03579-e03579, 2014

PubMed Abstract: Sodium/proton antiporters maintain intracellular pH and sodium levels. Detailed structures of antiporters with bound substrate ions are essential for understanding how they work. We have resolved the substrate ion in the dimeric, electroneutral sodium/proton antiporter PaNhaP from Pyrococcus abyssi at 3.2 Å, and have determined its structure in two different conformations at pH 8 and pH 4. The ion is coordinated by three acidic sidechains, a water molecule, a serine and a main-chain carbonyl in the unwound stretch of trans-membrane helix 5 at the deepest point of a negatively charged cytoplasmic funnel. A second narrow polar channel may facilitate proton uptake from the cytoplasm. Transport activity of PaNhaP is cooperative at pH 6 but not at pH 5. Cooperativity is due to pH-dependent allosteric coupling of protomers through two histidines at the dimer interface. Combined with comprehensive transport studies, the structures of PaNhaP offer unique new insights into the transport mechanism of sodium/proton antiporters.

PubMed: 25426802
DOI: 10.7554/eLife.03579

実験手法

X-RAY DIFFRACTION (3.2 Å)