Staphylococcus epidermidis, and other Staphylococcus spp. (e.g., S.aureus, S.haemolyticus, S.saprophyticus, S.hyicus,
S.simulans), is catalase positive. Catalase is a common enzyme found in nearly all living organisms exposed to oxygen.
It catalyzes the decomposition of hydrogen peroxide (3% water solution) to water and oxygen.