Biochemistry · Free Radicals, Antioxidant Defence and Xenobiotic Metabolism

Glutathione peroxidase detoxifies hydrogen peroxide and lipid hydroperoxides using reduced glutathione. Which trace element is an essential component of this enzyme?

  • A Zinc
  • B Selenium
  • C Manganese
  • D Copper
Correct answer: B. Selenium

Explanation

Glutathione peroxidase is a selenoenzyme: selenium sits at the active site as selenocysteine and participates directly in electron transfer from GSH to peroxide. Zinc is a cofactor for many enzymes but not this one; manganese belongs to mitochondrial MnSOD and copper-zinc to cytosolic SOD, so those options belong to a different antioxidant enzyme family.

Reference: Harper's Illustrated Biochemistry, 32nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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