A Mutation Results in the Change of Ser to Asp

question 94

Multiple Choice

A mutation results in the change of Ser to Asp in the substrate binding pocket of chymotrypsin.Most likely,the mutant enzyme will

• A) no longer catalyze the hydrolysis of a peptide bond because Asp cannot facilitate the nucleophilic attack.
• B) no longer catalyze the hydrolysis of a peptide bond because Asp is unable to be deprotonated by His57.
• C) preferentially hydrolyze substrates containing phenylalanine.
• D) preferentially hydrolyze substrates containing lysine.