Hydrogen peroxide is the end product of oxygen reduction by the terminal oxidase in the marine bacterium Pseudomonas nautica 617

AbstractMitochondrial cytochrome-c oxidase as well as several bacterial oxidases are known to reduce dioxygen to water. For the first time, a heme-containing oxidase, the terminal enzyme of the aerobic respiratory system in the marine bacterium Pseudomonas nautica 617, is shown to reduce molecular oxygen only to hydrogen peroxide. Whereas the cell content is well protected from H2O2, by catalase, the possible efflux of H2O2, into seawater could play an important role in the environment