Spread the love

Definition: How do allosteric enzyme inhibitors and activators work?

Allosteric enzyme inhibitors and activators are molecules that bind to a specific site on an enzyme, known as the allosteric site, to modulate its activity. Unlike competitive inhibitors, which bind to the active site of an enzyme and directly block substrate binding, allosteric inhibitors and activators exert their effects by inducing conformational changes in the enzyme.

When an allosteric inhibitor binds to the allosteric site, it stabilizes a conformational change in the enzyme that reduces its catalytic activity. This can occur by preventing the enzyme from binding to its substrate or by altering the active site’s shape, making it less favorable for substrate binding. As a result, the rate of the enzymatic reaction decreases.

See also Why are sirtuin activators considered caloric restriction mimetics?

On the other hand, allosteric activators bind to the allosteric site and induce a conformational change that enhances the enzyme’s catalytic activity. This can occur by promoting substrate binding or by increasing the enzyme’s affinity for the substrate. As a result, the rate of the enzymatic reaction increases.

The binding of allosteric inhibitors and activators to the allosteric site is often influenced by the concentration of other molecules in the cellular environment. For example, the binding of a specific metabolite may act as an allosteric activator for an enzyme involved in its synthesis, ensuring that the enzyme is only active when the metabolite is abundant.

See also What is the connection between TBIs and neurodegenerative diseases like Alzheimer's?

Overall, allosteric enzyme inhibitors and activators play a crucial role in regulating enzyme activity, allowing cells to fine-tune metabolic pathways and respond to changing environmental conditions.

Keywords: enzyme, allosteric, inhibitors, activators, binding, substrate, activity, active, conformational