Catalase

Definition

Catalase is an enzyme that catalyzes the decomposition of hydrogen peroxide to water and oxygen. It plays a crucial role in protecting cells from oxidative damage by reactive oxygen species.

5 Must Know Facts For Your Next Test

1. Catalase is commonly found in nearly all living organisms exposed to oxygen, including bacteria, plants, and animals.
2. The presence of catalase can be tested using the catalase test, where oxygen bubbles are observed when hydrogen peroxide is added to a microbial sample.
3. Catalase helps aerobic bacteria survive by breaking down toxic hydrogen peroxide produced during metabolic processes.
4. A lack of catalase activity can increase susceptibility to oxidative stress and damage within cells.
5. Some pathogenic bacteria produce catalase as a virulence factor to neutralize the host's immune response.

Review Questions

• What chemical reaction does catalase facilitate?
• Why is catalase important for aerobic microorganisms?
• Describe how the catalase test is performed and what a positive result indicates.

Related terms

Hydrogen Peroxide: A reactive oxygen species that can cause cellular damage but is broken down by catalase.

Oxidative Stress: A condition caused by an imbalance between free radicals and antioxidants in the body.

Virulence Factor: A molecule produced by pathogens that contributes to their ability to cause disease.