Which of the Following Elements Is Involved in the Mechanism

question 21

Multiple Choice

Which of the following elements is involved in the mechanism of chymotrypsin?

• A)deprotonation of an active site Asp residue by His to start the reaction
• B)formation of an acyl-enzyme intermediate that must be hydrolyzed to complete the reaction
• C)stabilization of the positively charged His by a Gln residue
• D)direct deprotonation of water by His to generate a hydroxide ion for initiation of the reaction

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