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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Which of the following amino acid contains free sulphydryl group -
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The correct answer is  Ans. is 'a' i.e., Cysteine o There are two sulfur containing amino acids :-i) Cysteineii) Methionineo The side chain of cysteine contains sulfhydryl group that has a pKa of approximately 8.4 for dissociation of its hydrogen sulfhydryl groups of two cystein molecules can form covalent disulfide bond to form cystineo Methionine although it contains sulfur group, does not containt sulfhydryl group and cannot form disulfide bond.