Protein Domain : CopK superfamily IPR038644

Type	Homologous_superfamily
Description	Copper resistance protein K (CopK) is a periplasmic dimeric protein which is strongly up-regulated in the presence of copper, leading to a high periplasmic accumulation [ , ]. CopK has two different binding sites for Cu(I), each with a different affinity for the metal. Binding of the first Cu(I) ion (CuI) induces a conformational change of CopK which involves dissociation of the dimeric apo-protein. Binding of a second Cu(I) (CuII) further increases the plasticity of the protein. The binding of CuI greatly enhances the specific affinity for CuII and, in turn, CuII binding increases the specific affinity for CuI, although to a lesser extent. This type of cooperative behaviour is unprecedented in copper binding proteins []. CopK has features that are common with functionally related proteins such as a structure consisting of an all-beta fold and a methionine-rich Cu(I) binding site [].
Short Name	CopK_sf