Stable Cu(II) and Cu(I) mononuclear intermediates in the assembly of the CuA center of Thermus thermophilus cytochrome oxidase.

ABSTRACT: CuA is a dinuclear mixed-valence center located in subunit 2 of the ba(3)-type cytochrome oxidase from Thermus thermophilus. The assembly of this site within the periplasmic membrane is believed to be mediated by the copper chaperones Sco and/or PCuAC, but the biological mechanisms are still poorly understood, thereby stimulating interest in the mechanisms of CuA formation from inorganic ions. The formulation of the CuA center as an electron-delocalized Cu(1.5)-Cu(1.5) system implicates both Cu(II) and Cu(I) states in the metalation process. In earlier work we showed that selenomethionine (SeM) substitution of the coordinated M160 residue provided a ligand-directed probe for studying the copper coordination environment via the Se XAS signal, which was particularly useful for interrogating

SUBMITTER: Chacon KN 

PROVIDER: S-EPMC3616644 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature