The difference in the minimal amount of H2O2 required to fully oxidize HyPer-3 and roGFP2-Orp1 in vitro (20 μM and 5 μM, respectively) and in living malaria parasites (1 mM) is likely due to the antioxidant capacity of the parasite-host cell unit including catalase and peroxiredoxins [37]. This evidence concerns the gene CAT and malaria.