Some 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:
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