2NNX

Crystal Structure of the H46R, H48Q double mutant of human [Cu-Zn] Superoxide Dismutase

2NNX の概要

• エントリーDOI: 10.2210/pdb2nnx/pdb
• 分子名称: SUPEROXIDE DISMUTASE [CU-ZN], ZINC ION, SULFATE ION, ... (4 entities in total)
• 機能のキーワード: oxidoreductase; human; cu-zn superoxide dismutase; superoxide acceptor; familial amyotrophic lateral sclerosis mutant, oxidoreductase
• 由来する生物種: Homo sapiens (human)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 64069.85

構造登録者

Schuermann, J.P.,Hart, P.J. (登録日: 2006-10-24, 公開日: 2006-11-07, 最終更新日: 2024-11-13)

主引用文献

Wang, J.,Caruano-Yzermans, A.,Rodriguez, A.,Scheurmann, J.P.,Slunt, H.H.,Cao, X.,Gitlin, J.,Hart, P.J.,Borchelt, D.R.
Disease-associated mutations at copper ligand histidine residues of superoxide dismutase 1 diminish the binding of copper and compromise dimer stability
J.Biol.Chem., 282:345-352, 2007

PubMed Abstract: A subset of superoxide dismutase 1 (Cu/Zn-SOD1) mutants that cause familial amyotrophic lateral sclerosis (FALS) have heightened reactivity with (-)ONOO and H(2)O(2) in vitro. This reactivity requires a copper ion bound in the active site and is a suggested mechanism of motor neuron injury. However, we have found that transgenic mice that express SOD1-H46R/H48Q, which combines natural FALS mutations at ligands for copper and which is inactive, develop motor neuron disease. Using a direct radioactive copper incorporation assay in transfected cells and the established tools of single crystal x-ray diffraction, we now demonstrate that this variant does not stably bind copper. We find that single mutations at copper ligands, including H46R, H48Q, and a quadruple mutant H46R/H48Q/H63G/H120G, also diminish the binding of radioactive copper. Further, using native polyacrylamide gel electrophoresis and a yeast two-hybrid assay, the binding of copper was found to be related to the formation of the stable dimeric enzyme. Collectively, our data demonstrate a relationship between copper and assembly of SOD1 into stable dimers and also define disease-causing SOD1 mutants that are unlikely to robustly produce toxic radicals via copper-mediated chemistry.

PubMed: 17092942
DOI: 10.1074/jbc.M604503200

実験手法

X-RAY DIFFRACTION (2.3 Å)