Question

A mutation of the proteolytic enzyme Trypsin (described in Section 6.1) results in a stable covalent bond between one of the catalytic amino acids of the protease and its protein substrate. Which of the following are probably true?
a. The enzyme would become inactive.
b. The enzyme and substrate would be stuck together.
c. The delta-G of the proteolysis reaction would change.
d. The rate of the catalyzed reaction would increase.

Answer 1

Answer:

b. The enzyme and substrate would be stuck together.

Explanation:

Enzymes are proteins whose active site binds to specific chemical reactants (i.e., substrates), thereby forming a complex that is similar to the interaction between a lock and its key. This active complex lowers the energy of the reaction and promotes a conformational change in the substrate to break down it into multiple products. When the enzyme contains mutations in its active site, the ability to bind the substrate is altered. In this case, the enzymatic reaction can't occur because the interaction enzyme-substrate doesn't produce an active complex.