Multimetal Oxidases

In this chapter, we focus on the protein copper coordination chemistry in which dioxygen activation at heme-copper or multinuclear copper centers leads to the four-electron four-proton reduction of O₂ to water. These reactions are coupled to substrate oxidations as well as proton translocation in the case of cytochrome c oxidase. The last few years of the twentieth century saw considerable research advances in protein X-ray structures and insights into the O₂-binding and mechanisms of the reductive O—O cleavage process. We highlight here these structural and mechanistic advances, as well as aspects of synthetic model chemistry being carried out to mimic or provide additional insights into the fundamental metal–dioxygen chemistry involved.