Which trace element is the metal cofactor of the mitochondrial isoform of superoxide dismutase?

• A Manganese ✓
• B Iron
• C Zinc and copper
• D Selenium

Explanation

Mitochondrial superoxide dismutase (MnSOD, SOD2) contains manganese at its active site and detoxifies superoxide generated by the electron transport chain. Cytosolic SOD1 uses copper and zinc, extracellular SOD3 also uses copper and zinc, and selenium functions in glutathione peroxidase rather than SOD. Chronic inhalational exposure to manganese dust, incidentally, causes manganism, a parkinsonian syndrome relevant to occupational toxicology.

Reference: Harper's Illustrated Biochemistry, 31st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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