Chapter 20, Problem 20.80AQAP

Interpretation Introduction

Interpretation:

The three types of inhibitors have to be matched with the given four statements.

Concept Introduction:

Irreversible inhibition is a type of inhibition in which a molecule (inhibitor) reacts with the enzyme and changes it chemically for example via a covalent bond formation. This type of inhibition usually renders the enzyme denatured. An example of irreversible inhibitor is penicillin. It inhibits the activity of the enzymes responsible for the formation of bacterial cell wall.

Reversible inhibition is a type of inhibition in which a molecule (inhibitor) reacts with the enzyme and once removed lets the enzyme it was inhibiting to work again normally. It does not result in any permanent effects on the enzyme. In other words, reversible inhibitors of an enzyme bind non-covalently to it. Reversible inhibition is of three different types namely: Competitive, Non-competitive, uncompetitive.

Competitive reversible inhibition : In this kind of inhibition, the inhibitor molecule has some structural similarity to the normal substrate. Hence the inhibitor binds to the active site and prevents the normal substrate binding to the enzyme.

Non-competitive reversible inhibition: In this kind of inhibition, the inhibitor molecule binds to a different site that is not the active site of the enzyme and changes the structure of the enzyme; therefore, it blocks the enzyme from binding to the substrate, which stops enzyme activity.