In biochemistry, allosteric (from the Greek "allos" = different, "stereos" = fixed) describes the property of a protein - for example an enzyme or a receptor - to be influenced by the binding of a molecule to a site other than the active center.
Allosteric
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General informationThis section has been translated automatically.
An allosteric protein has:
- an active center (where the substrate binds) and
- an allosteric center (where a regulator molecule can bind).
When a molecule binds to the allosteric center of e.g. a receptor protein, this binding changes the spatial structure of the protein. This can have two effects:
- Activation: The active site becomes more accessible: Enzyme/receptor becomes more active
- Inhibition: The spatial structure of the active site is distorted or blocked: Enzyme/receptor is inhibited
Example of "allosteric inhibition": An inhibitor binds to the allosteric center of a kinase. The kinase changes its molecular structure. The substrate no longer fits into the active center. The activity decreases.
Significance in medicine: Allosteric modulation is important in the development of drugs because it can regulate more specifically (finer control than direct blockade) and often has fewer side effects.