4WIB

Crystal structure of Magnesium transporter MgtE

4WIB の概要

• エントリーDOI: 10.2210/pdb4wib/pdb
• 分子名称: Magnesium transporter MgtE, CALCIUM ION (2 entities in total)
• 機能のキーワード: channel, magnesium, transporter, metal transport
• 由来する生物種: Thermus thermophilus HB8
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 38580.15

構造登録者

Takeda, H.,Hattori, M.,Nishizawa, T.,Yamashita, K.,Shah, S.T.A.,Caffrey, M.,Maturana, A.D.,Ishitani, R.,Nureki, O. (登録日: 2014-09-25, 公開日: 2014-12-03, 最終更新日: 2024-03-20)

主引用文献

Takeda, H.,Hattori, M.,Nishizawa, T.,Yamashita, K.,Shah, S.T.,Caffrey, M.,Maturana, A.D.,Ishitani, R.,Nureki, O.
Structural basis for ion selectivity revealed by high-resolution crystal structure of Mg(2+) channel MgtE
Nat Commun, 5:5374-5374, 2014

PubMed Abstract: Magnesium is the most abundant divalent cation in living cells and is crucial to several biological processes. MgtE is a Mg(2+) channel distributed in all domains of life that contributes to the maintenance of cellular Mg(2+) homeostasis. Here we report the high-resolution crystal structures of the transmembrane domain of MgtE, bound to Mg(2+), Mn(2+) and Ca(2+). The high-resolution Mg(2+)-bound crystal structure clearly visualized the hydrated Mg(2+) ion within its selectivity filter. Based on those structures and biochemical analyses, we propose a cation selectivity mechanism for MgtE in which the geometry of the hydration shell of the fully hydrated Mg(2+) ion is recognized by the side-chain carboxylate groups in the selectivity filter. This is in contrast to the K(+)-selective filter of KcsA, which recognizes a dehydrated K(+) ion. Our results further revealed a cation-binding site on the periplasmic side, which regulate channel opening and prevents conduction of near-cognate cations.

PubMed: 25367295
DOI: 10.1038/ncomms6374

実験手法

X-RAY DIFFRACTION (3.2 Å)