title: CzcE from Cupriavidus metallidurans CH34 is a copper-binding protein.
abstract: CzcE is encoded by the most distal gene of the czc determinant that allows Cupriavidus metallidurans CH34 to modulate its internal concentrations of cobalt, zinc and cadmium by regulation of the expression of the efflux pump CzcCBA. We have overproduced and purified CzcE. CzcE is a periplasm-located dimeric protein able to bind specifically 4 Cu-equivalent per dimer. Spectrophotometry and EPR are indicative of type II copper with typical d-d transitions. Re-oxidation of fully reduced CzcE led to the formation of an air stable semi-reduced form binding both 2 Cu(I) and 2 Cu(II) ions. The spectroscopic characteristics of the semi-reduced form are different of those of the oxidized one, suggesting a change in the environment of Cu(II).
authors.affiliation: Laboratoire des Protéines Membranaires, Institut de Biologie Structurale-Jean-Pierre Ebel, UMR 5075 CNRS-CEA-UJF, 41, rue Jules Horowitz, 38027 Grenoble Cedex, France.
authors.forename: Anthony
authors.initials: A
authors.lastname: Zoropogui
authors.forename: Serge
authors.initials: S
authors.lastname: Gambarelli
authors.forename: Jacques
authors.initials: J
authors.lastname: Covès
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D001665:Binding Sites; D003300:Copper / Q000737:chemistry*; D049921:Cupriavidus / Q000737:chemistry*; D011485:Protein Binding
chemical_list: D001426:Bacterial Proteins; D003300:Copper