Microbiology: Catalase Test

The video explains the catalase test, an important method to differentiate between catalase-producing bacteria like Staphylococcus and non-producers like Streptococcus. Catalase is an enzyme that converts hydrogen peroxide into water and oxygen, preventing damage from radicals. The test is positive if bubbles form after adding hydrogen peroxide, indicating catalase presence. Humans also produce catalase, which can be observed when hydrogen peroxide is applied to wounds, causing bubbling. The video provides visual examples of positive and negative test results.

What is the primary function of the catalase enzyme?

• To produce hydrogen peroxide

• To detoxify hydrogen peroxide into water and oxygen

• To create radicals

• To damage DNA and proteins

Which bacteria are known to produce catalase?

• Both Streptococci and Staphylococci

• Streptococci

• Neither Streptococci nor Staphylococci

• Staphylococci

What observable effect does catalase have when hydrogen peroxide is applied to a wound?

• It changes the color of the skin

• It causes the wound to heal instantly

• It produces a burning sensation

• It creates bubbles

How can you tell if a bacterium is catalase-positive?

• By the absence of bubbles

• By the presence of bubbles

• By a change in temperature

• By a change in color

What result would you expect from a catalase test on Streptococcus?

• Bubbles are produced

• No bubbles are produced

• The solution turns blue

• The solution heats up