Catalase Test

bacteria produce the enzyme catalase, which is an iron porphyrin protein  This enzyme is responsible for the decomposition of hydrogen peroxide to water and oxygen   H2O2 CATALASE H2O + O2    Procedures: 

 Some

Emulsify about 1 or 2 colonies of Staphylococcus organism from a plate culture with a drop of saline on a slide. Add a drop of hydrogen peroxide. Observe for air bubbles



Observation:



Positive test • presence of air bubbles • Bubbling upon the addition of hydrogen peroxide is indicative of the presence of catalase for this organism. • Note, most aerobic organism make catalase. • Differentiates Staphylococcus from Streptococcus All Staph (+) All Strep (-)



Negative test – no air bubbles