Metal coordination and mechanism of multicopper nitrite reductase.
Cu-containing nitrite reductase is a homotrimer in which a ca. 36 kDa monomer contains each of type 1 Cu (two His, Cys, and Met ligands) and type 2 Cu (three His and solvent ligands). Type 1 Cu receives one electron from an electron donor and transfers it to the reaction center, type 2 Cu. The distance between the two Cu atoms bound by the Cys-His sequence segment is 12.6 A. The intramolecular electron transfer from type 1 Cu to type 2 Cu occurs probably through this segment. The noncoordinated Asp and His residues around type 2 Cu play important roles in both the electron-transfer and the catalytic processes.
Suzuki
S
S
Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan. bic@ch.wani.osaka-u.ac.jp
Kataoka
K
K
Yamaguchi
K
K
D003300:Copper / Q000737:chemistry*; D004583:Electrons; D008958:Models, Molecular; D009572:Nitrite Reductases / Q000737:chemistry*; D009573:Nitrites / Q000737:chemistry; D010084:Oxidation-Reduction; D011487:Protein Conformation
D009573:Nitrites; D003300:Copper; D009572:Nitrite Reductases; C052695:nitrite reductase, copper-containing