O2-Evolving Chlorite Dismutase as a Tool for Studying O2-Utilizing Enzymes

Abstract
The direct interrogation of fleeting intermediates by rapid-mixing kinetic methods has significantly advanced our understanding of enzymes that utilize dioxygen. The gas’s modest aqueous solubility (6 mM in IV–oxo complex, J, in taurine:α-ketoglutarate dioxygenase and superoxo–Fe2III/III complex, G, in myo-inositol oxygenase, and the tyrosyl-radical-generating Fe2III/IV intermediate, X, in Escherichia coli RNR, were all accumulated to yields more than twice those previously attained. This means of in situ O2 evolution permits a >5 mM “pulse” of O2 to be generated in 2 addition steps.