Mechanism of cytochrome c oxidase-catalyzed reduction of dioxygen to water: evidence for peroxy and ferryl intermediates at room temperature

Peroxy and ferryl species are formed as intermediates during the reduction of dioxygen by cytochrome c oxidase at room temperature. The ferrous-oxy compound attains maximum concentration 30 micro seconds after photolysis, and decays into the peroxy species. The peroxy species decays into the ferryl intermediate which has a peak at 578 nm. The maximum concentration of the ferryl species is reached after 310 micro seconds of photolysis. The agreement between the results from theoretical and experimental spectra confirms the presence of peroxy and ferryl intermediates.