1SL7

Crystal structure of calcium-loaded apo-obelin from Obelia longissima

1SL7 の概要

• エントリーDOI: 10.2210/pdb1sl7/pdb
• 関連するPDBエントリー: 1EJ3 1EL4 1JF0 1JF2 1QV0 1QV1 1S36
• 分子名称: Obelin, CALCIUM ION (3 entities in total)
• 機能のキーワード: photoprotein, obelin, bioluminescence, calcium binding, ef-hand, aequorin, fluorescence, structural genomics, psi, protein structure initiative, southeast collaboratory for structural genomics, secsg, luminescent protein
• 由来する生物種: Obelia longissima
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 22376.13

構造登録者

Deng, L.,Markova, S.V.,Vysotski, E.S.,Liu, Z.J.,Lee, J.,Rose, J.,Wang, B.C.,Southeast Collaboratory for Structural Genomics (SECSG) (登録日: 2004-03-05, 公開日: 2004-12-28, 最終更新日: 2023-08-23)

主引用文献

Deng, L.,Vysotski, E.S.,Markova, S.V.,Liu, Z.J.,Lee, J.,Rose, J.,Wang, B.C.
All three Ca2+-binding loops of photoproteins bind calcium ions: The crystal structures of calcium-loaded apo-aequorin and apo-obelin.
Protein Sci., 14:663-675, 2005

PubMed Abstract: The crystal structures of calcium-loaded apo-aequorin and apo-obelin have been determined at resolutions 1.7A and 2.2 A, respectively. A calcium ion is observed in each of the three EF-hand loops that have the canonical calcium-binding sequence, and each is coordinated in the characteristic pentagonal bipyramidal configuration. The calcium-loaded apo-protein retain the same compact scaffold and overall fold as the unreacted photoproteins containing the bound substrate, 2-hyroperoxycoelenterazine, and also the same as the Ca2+-discharged obelin bound with product, coleneteramide. Nevertheless, there are easily discerned shifts in both helix and loop regions, and the shifts are not the same between the two proteins. It is suggested that these photoproteins to sense Ca2+ concentration transients and to produce their bioluminescence response on the millisecond timescale. A mechanism of intrastructural transmission of the calcium signal is proposed.

PubMed: 15689515
DOI: 10.1110/ps.041142905

実験手法

X-RAY DIFFRACTION (2.2 Å)