CopC is a bacterial blue copper protein that binds 1 atom of copper per protein molecule. Along with CopA, CopC mediates copper resistance by sequestration of copper in the periplasm [1].

1: Copper resistance in Pseudomonas syringae mediated by periplasmic and outer membrane proteins. Cha JS, Cooksey DA; Proc Natl Acad Sci U S A 1991;88:8915-8919. PMID:1924351