5. Enzyme inhibitors

The inhibition of an enzyme involved in a pathology of metabolic origin can contribute to the creation of new drugs (see the case of fexofenadine). However, inhibition of an enzyme (E) by a substrate (S) can take different forms: it can be reversible or irreversible. In the first case, the (E-S) bond is weak (hydrogen, electrostatic, Van der Waals or hydrophobic bonds) and allows the enzyme to recover its activity after a more or less prolonged delay. In the second case, the inhibitor is irreversible and strong, of the covalent type, and concerns the catalytic site of the enzyme, whose activity is only regained after a prolonged period, essential for the organism to develop a new biosynthesis. The choice of inhibitor will therefore depend on the therapeutic objective pursued.

On the other hand, a large number of enzymes are active in humans, as well as in parasites,...