Structure and function of type I copper in multicopper oxidases
- First Online:
- Cite this article as:
- Sakurai, T. & Kataoka, K. Cell. Mol. Life Sci. (2007) 64: 2642. doi:10.1007/s00018-007-7183-y
- 579 Downloads
The type I copper center in multicopper oxidases is constructed from 1Cys2His and weakly coordinating 1Met or the non-coordinating 1Phe/1Leu, and it exhibits spectral properties and an alkaline transition similar to those of the blue copper center in blue copper proteins. Since the type I copper center in multicopper oxidases is deeply buried inside the protein molecule, electron transfers to and from type I copper are performed through specific pathways: the hydrogen bond between an amino acid located at the substrate binding site and a His residue coordinating type I copper, and the His-Cys-His sequence connecting the type I copper center and the trinuclear copper center comprised of a type II copper and a pair of type III coppers. The intramolecular electron transfer rates can be tuned by mutating the fourth ligand of type I copper. Further, mutation at the Cys ligand gives a vacant type I copper center and traps the reaction intermediate during the four-electron reduction of dioxygen.