Involved in uptake of extracellular oxidized copper under copper-limiting conditions. Highly induced under copper-limiting conditions. Down-regulated by YcnK, especially under high copper concentrations. Down-regulated by CsoR. Cells lacking this gene show a growth-defective phenotype under copper deprivation as well as a reduced intracellular content of copper. In the N-terminal section; belongs to the CopC family. In the C-terminal section; belongs to the CopD family.