Investigation of the fine structure around the copper site in copper/zinc superoxide dismutase by XANES combined with ab initio calculations
Abstract
Copper/zinc superoxide dismutase (CuZnSOD) is an important enzyme that plays a crucial role in protecting oxygen-metabolizing cells against harmful effects of superoxide free-radicals. In this work, the three-dimensional local structure around the copper-binding site in pH 7.0 buffer solution was determined using X-ray absorption near-edge spectroscopy (XANES) combined with ab initio calculations in the framework of the multiple-scattering theory performed by MXAN. Extremely accurate bond distances and bond angle information between ligands were returned. The result confirmed that the copper ion binds four conserved His residues and a water molecule in CuZnSOD and prefers a five-coordinated in a distorted square pyramidal geometry.
- Publication:
-
Radiation Physics and Chemistry
- Pub Date:
- August 2017
- DOI:
- 10.1016/j.radphyschem.2016.03.003
- Bibcode:
- 2017RaPC..137...88W
- Keywords:
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- Copper/zinc superoxide dismutase;
- BioXAS;
- Metalloprotein;
- MXAN