2C9M

Structure of (SR) Calcium-ATPase in the Ca2E1 state solved in a P1 crystal form.

2C9M の概要

• エントリーDOI: 10.2210/pdb2c9m/pdb
• 関連するPDBエントリー: 1FQU 1IWO 1KJU 1SU4 1T5S 1T5T 1VFP 1WPE 1WPG 1XP5 2AGV 2BY4 2C88 2C8K 2C8L
• 分子名称: SARCOPLASMIC/ENDOPLASMIC RETICULUM CALCIUM ATPASE 1, CALCIUM ION, POTASSIUM ION, ... (4 entities in total)
• 機能のキーワード: ca2+-atpase, p-type atpase, cation pump, membrane protein, modulatory atp, hydrolase, atp-binding, calcium transport, ion transport, metal-binding, nucleotide-binding, phosphorylation
• 由来する生物種: ORYCTOLAGUS CUNICULUS (RABBIT)
• 細胞内の位置: Endoplasmic reticulum membrane; Multi-pass membrane protein: P04191
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 219634.80

構造登録者

Lund Jensen, A.-M.,Sorensen, T.L.-M.,Olesen, C.,Moller, J.V.,Nissen, P. (登録日: 2005-12-13, 公開日: 2006-12-18, 最終更新日: 2024-11-06)

主引用文献

Lund Jensen, A.-M.,Sorensen, T.L.-M.,Olesen, C.,Moller, J.V.,Nissen, P.
Modulatory and Catalytic Modes of ATP Binding by the Calcium Pump
Embo J., 25:2305-, 2006

PubMed Abstract: We present crystal structures of the calcium-free E2 state of the sarcoplasmic reticulum Ca2+ -ATPase, stabilized by the inhibitor thapsigargin and the ATP analog AMPPCP. The structures allow us to describe the ATP binding site in a modulatory mode uncoupled from the Asp351 phosphorylation site. The Glu439 side chain interacts with AMPPCP via an Mg2+ ion in accordance with previous Fe2+ -cleavage studies implicating this residue in the ATPase cycle and in magnesium binding. Functional data on Ca2+ mediated activation indicate that the crystallized state represents an initial stage of ATP modulated deprotonation of E2, preceding the binding of Ca2+ ions in the membrane from the cytoplasmic side. We propose a mechanism of Ca2+ activation of phosphorylation leading directly from the compact E2-ATP form to the Ca2E1-ATP state. In addition, a role of Glu439 in ATP modulation of other steps of the functional cycle is suggested.

PubMed: 16710301
DOI: 10.1038/SJ.EMBOJ.7601135

実験手法

X-RAY DIFFRACTION (3 Å)