KROK 1 2014 – Question 56 · KROK (Medicine) · Biological Chemistry
Those organisms which in the process of evolution failed to develop protection from H₂O₂ can exist only in anaerobic conditions. Which of the following enzymes can break hydrogen peroxide down?
- A. Peroxidase and catalase
- B. Cytochrome oxidase, cytochrome B5
- C. Oxygenase and catalase
- D. Oxygenase and hydroxylase
- E. Flavin-dependent oxidase
Hint
Think about which enzymes form the antioxidant defence of aerobic cells against this reactive oxygen species, and why anaerobes lacking them cannot tolerate oxygen.
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