Cooperation between two periplasmic copper chaperones is required for full activity of the cbb3 -type cytochrome c oxidase and copper homeostasis in Rhodobacter capsulatus.

ABSTRACT: Copper (Cu) is an essential micronutrient that functions as a cofactor in several important enzymes, such as respiratory heme-copper oxygen reductases. Yet, Cu is also toxic and therefore cells engage a highly coordinated Cu uptake and delivery system to prevent the accumulation of toxic Cu concentrations. In this study, we analyzed Cu delivery to the cbb3 -type cytochrome c oxidase (cbb3 -Cox) of Rhodobacter capsulatus. We identified the PCuA C-like periplasmic chaperone PccA and analyzed its contribution to cbb3 -Cox assembly. Our data demonstrate that PccA is a Cu-binding protein with a preference for Cu(I), which is required for efficient cbb3 -Cox assembly, in particular, at low Cu concentrations. By using in vivo and in vitro cross-linking, we show that PccA forms a complex with the

SUBMITTER: Trasnea PI 

PROVIDER: S-EPMC4878679 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature