Nickel superoxide dismutase structure and mechanism.

  title={Nickel superoxide dismutase structure and mechanism.},
  author={David P. Barondeau and Carey J Kassmann and Cami K. Bruns and John A. Tainer and Elizabeth D. Getzoff},
  volume={43 25},
The 1.30 A resolution crystal structure of nickel superoxide dismutase (NiSOD) identifies a novel SOD fold, assembly, and Ni active site. NiSOD is a hexameric assembly of right-handed 4-helix bundles of up-down-up-down topology with N-terminal hooks chelating the active site Ni ions. This newly identified nine-residue Ni-hook structural motif (His-Cys-X-X-Pro-Cys-Gly-X-Tyr) provides almost all interactions critical for metal binding and catalysis, and thus will likely be diagnostic of NiSODs… 

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