1EXR

THE 1.0 ANGSTROM CRYSTAL STRUCTURE OF CA+2 BOUND CALMODULIN

1EXR の概要

• エントリーDOI: 10.2210/pdb1exr/pdb
• 関連するPDBエントリー: 1CLM 1OSA
• 分子名称: CALMODULIN, CALCIUM ION (3 entities in total)
• 機能のキーワード: calmodulin, high resolution, disorder, metal transport
• 由来する生物種: Paramecium tetraurelia
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 16887.81

構造登録者

Wilson, M.A.,Brunger, A.T. (登録日: 2000-05-03, 公開日: 2000-09-20, 最終更新日: 2024-04-03)

主引用文献

Wilson, M.A.,Brunger, A.T.
The 1.0 A crystal structure of Ca(2+)-bound calmodulin: an analysis of disorder and implications for functionally relevant plasticity
J.Mol.Biol., 301:1237-1256, 2000

PubMed Abstract: Calmodulin (CaM) is a highly conserved 17 kDa eukaryotic protein that can bind specifically to over 100 protein targets in response to a Ca(2+) signal. Ca(2+)-CaM requires a considerable degree of structural plasticity to accomplish this physiological role; however, the nature and extent of this plasticity remain poorly characterized. Here, we present the 1.0 A crystal structure of Paramecium tetraurelia Ca(2+)-CaM, including 36 discretely disordered residues and a fifth Ca(2+) that mediates a crystal contact. The 36 discretely disordered residues are located primarily in the central helix and the two hydrophobic binding pockets, and reveal correlated side-chain disorder that may assist target-specific deformation of the binding pockets. Evidence of domain displacements and discrete backbone disorder is provided by translation-libration-screw (TLS) analysis and multiconformer models of protein disorder, respectively. In total, the evidence for disorder at every accessible length-scale in Ca(2+)-CaM suggests that the protein occupies a large number of hierarchically arranged conformational substates in the crystalline environment and may sample a quasi-continuous spectrum of conformations in solution. Therefore, we propose that the functionally distinct forms of CaM are less structurally distinct than previously believed, and that the different activities of CaM in response to Ca(2+) may result primarily from Ca(2+)-mediated alterations in the dynamics of the protein.

PubMed: 10966818
DOI: 10.1006/jmbi.2000.4029

実験手法

X-RAY DIFFRACTION (1 Å)