Question

Studies conducted with a lysozyme mutant that contains an Asp → Asn change at position 52 and a Glu Gln change at position 35 exhibited almost a complete loss in enzymatic activity. What is the most likely explanation for the decrease in enzyme activity in the mutant?

A) increased affinity for substrate
B) absence of negative charges in the active site
C) change in an allosteric site of the enzyme
D) larger amino acids in the active site decrease the affinity for substrate
E) None of the above

Answer 1

The decrease in enzyme activity in the lysozyme mutant is most likely due to a change in an allosteric site of the enzyme, which decreases the affinity of the active site for its substrate.

Step-by-step explanation:

The most likely explanation for the decrease in enzymatic activity in the lysozyme mutant with the Asp → Asn change at position 52 and Glu → Gln change at position 35 is that there is a change in an allosteric site of the enzyme. Allosteric inhibitors bind to an enzyme away from the active site and induce a conformational change that decreases the affinity of the enzyme's active site for its substrate. This change in conformation reduces the enzyme's enzymatic activity.