Chapter 3, Problem 3E

Summary Introduction

The enzyme pyruvate dehydrogenase transforms pyruvate into acetyl CoA. This particular enzyme can be activated by phosphorylation and deactivated by de-phosphorylation. This process of activation and inactivation can be taken as an example of covalent regulation.

Covalent regulation is a method of regulation of enzymes in which an enzyme is activated by the covalent bonding between the chemical compound and the active site of the enzyme where the chemical compound is catalyzed by the enzyme.

The covalent bonds are very strong in nature and hence the enzymes remain attached to the chemical reactant unless there is the action of another enzyme on this combined molecule to break the bond with the first enzyme.

Thus, covalent regulation is a process in which the addition and removal of the chemical group stimulate the activation and inactivation of the enzyme.