Allosterisiin

Allosterisiin refers to a phenomenon in biochemistry where the activity of a protein, typically an enzyme, is regulated by the binding of a molecule at a site other than the protein's active site. This regulatory molecule is known as an allosteric effector or allosteric modulator.

When an allosteric effector binds to its specific site on the protein, it induces a conformational change in the protein's three-dimensional structure. This change can either increase the protein's activity, a process called allosteric activation, or decrease its activity, known as allosteric inhibition. The active site of the protein becomes either more or less accessible or efficient at interacting with its substrate due to this conformational shift.

Allosteric regulation is a crucial mechanism for controlling metabolic pathways and cellular processes. It allows cells to respond dynamically to changes in their internal and external environments. For instance, many enzymes in metabolic pathways are subject to feedback inhibition, where the end product of the pathway acts as an allosteric inhibitor of an early enzyme. This prevents the overproduction of the end product. Conversely, some enzymes are activated by allosteric effectors that signal the need for a particular metabolic process. This type of regulation is highly specific, as allosteric effectors typically bind to their designated sites with high affinity.