In biochemistry, suicide inhibition, also known as suicide inactivation or mechanism-based inhibition, is an irreversible form of enzyme inhibition that occurs when an enzyme binds a substrate analogue and forms an irreversible complex with it through a covalent bond during the normal catalysis reaction. The inhibitor binds to the active site where it is modified by the enzyme to produce a reactive group that reacts irreversibly to form a stable inhibitor-enzyme complex. This usually uses a prosthetic group or a coenzyme, forming electrophilic alpha and beta unsaturated carbonyl compounds and imines.
Some clinical examples of suicide inhibitors include:
Suicide inhibitors are used in what is called "rational drug design" where the aim is to create a novel substrate, based on already known mechanisms and substrates. The main goal of this approach is to create substrates that are unreactive until within that enzyme's active site and at the same time being highly specific. Drugs based on this approach have the advantage of very few resulting side effects.