Oxygen‐Activating Enzymes, Chemistry of

Abstract

Aerobic organisms derive the energy required for cellular processes from the conversion of dioxygen to water, which highlights the importance of dioxygen chemistry in biologic systems. The biochemistry of dioxygen is far from simple and has been the subject of intense study in a range of chemical and biologic disciplines. The reduction of dioxygen is energetically favorable; however, dioxygen is a ground state triplet, kinetically unreactive with singlet organic molecules. Nature has developed a diverse array of catalysts to overcome this kinetic barrier. These dioxygen‐activating enzymes are divided into two classes: oxygenases and oxidases. Oxygenases incorporate directly at least one atom from dioxygen into the organic products of their reaction. Oxidases couple the reduction of dioxygen with the oxidation of substrate. Typically, enzymes that react with dioxygen contain transition metal ions and/or conjugated organic molecules as cofactors. The reaction with dioxygen is initiated by electron transfer from the cofactor to O 2 . The subsequent chemistry varies depending on both the nature of the cofactor and the protein scaffold. Here we review the fascinating chemistry of the dioxygen‐activating enzymes and identify some of the common strategies and themes that have emerged from over half a century of research.

Overview of the Stability of α-Chymotrypsin in Different Solvent Media

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“…Cooperative interactions between the metal centers can also be beneficial for reactivity. Indeed, the enzymes that catalyze small-molecule reactions commonly employ multiple metal cofactors, and both of the aforementioned effects are key to their reactivity . Consequently, numerous biomimetic homo- and heteronuclear complexes have been synthesized. , …”

Design and engineering of artificial oxygen-activating metalloenzymes

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