Question

1. predict the effect of mutating the aspartic acid at the active site of chymotrypsin to asparagine.

Explanation:

Chymotrypsin's active site aspartic acid is part of its catalytic triad (Asp, His, Ser), which is critical for the enzyme's proteolytic function. Mutating this negatively charged aspartic acid to uncharged asparagine disrupts the hydrogen-bonding network that stabilizes the catalytic triad's proton transfer. This eliminates the enzyme's ability to activate the serine residue for nucleophilic attack on peptide bonds.

Answer:

Mutating the active site aspartic acid of chymotrypsin to asparagine will completely abolish or drastically reduce the enzyme's catalytic activity, as it breaks the essential proton relay system of the catalytic triad required for chymotrypsin's proteolytic function.