This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Amino Acid Metabolism, Subject name: Biochemistry
[{'content': 'Role of selenocystein is important in - \nSelect and explain. \nA. Hydroxylation of dopamine, B. Oxidation of drugs, C. Antioxidant mechanism, D. None of the above', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Antioxidant mechanism o Selenocysteine is considered to 21st standard amino acid.o It is present at the active site of many enzymesGlutathione peroxidase - An antioxidant enzyme.Deiodinase - Converts T4 to T3iii) Thioredoxin reductase.Glycine reductase.Formate dehydrogenaseo Selenocysteine has a structure similar in cystein, but containing selenium in place of sulfur atom of cysteine,o Proteins that contain selenocystein residues are called selenoproteins.", 'role': 'assistant'}]