Feedback inhibition A mode of enzyme regulation in which the end product of a biosynthetic pathway inhibits the enzyme that catalyzes the first step in that pathway.
In feedback inhibition, the allosteric effect lowers the affinity of the enzyme for its substrate.
In precursor activation, the regulator molecule increases the affinity of the enzyme in the series for its substrate.
Negative feedback inhibition is like a thermostat. When it is cold, the thermostat turns on a heater which produces heat. Heat causes the thermostat to turn off the heater.
Citrate is used for feedback inhibition, as it inhibits phosphofructokinase, an enzyme involved in glycolysis that catalyses formation of fructose 1,6-bisphosphate, a precursor of pyruvate.
The released hormones dampen the production of these hormones by feedback inhibition to avoid overproduction.
Availability of the hormone in the cytosol. Several hormones can be converted into a storage form by the target cell for later use.
Binding of an allosteric effector changes the shape of the enzyme, inactivating it while the effector is still bound. Such a mechanism is commonly employed in feedback inhibition.
 See also: Trans, Cell, Enzyme, Protein, Molecule
  
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