Inhibition of an enzyme is irreversible when
A) a competitive inhibitor is involved.
B) a noncompetitive inhibitor is involved.
C) there is an abundance of substrate.
D) covalent bonds form between inhibitor and enzyme.

Question

Quizplus · Accepted Answer

Irreversible inhibition occurs when covalent bonds form between the inhibitor and the enzyme, permanently altering its active site and inhibiting its function even after the inhibitor is removed. Choices A and B represent reversible inhibition, where the inhibitor is not permanently bound to the enzyme and can be displaced by increasing substrate concentration or other means. Choice C refers to saturation kinetics and does not necessarily entail any inhibition.

Inhibition of an Enzyme Is Irreversible When