Which subcellular organelle houses the highest concentration of catalase, the enzyme that converts two molecules of hydrogen peroxide to water and oxygen without consuming a reducing cofactor?
- A Mitochondria
- B Smooth endoplasmic reticulum
- C Peroxisomes ✓
- D Lysosomes
Correct answer: C. Peroxisomes
Explanation
Catalase is concentrated in peroxisomes, where it destroys the large flux of H2O2 generated by peroxisomal oxidases such as D-amino acid oxidase, urate oxidase and fatty acyl-CoA oxidase. The smooth ER contains the cytochrome P450 system, mitochondria contain MnSOD rather than catalase, and lysosomes rely on acid hydrolases, so none of these is the main catalase store.
Reference: Harper's Illustrated Biochemistry, 32nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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