The term feedback inhibition refers to a situation in which the substances at the end of a long series of reactions inhibits a reaction at the begining of the series of reactions. For example
In this chain of reactions substances A is convered to substance B which is in turn converted to substance C.
Substance C then can be used in other reactions. As long as substance C is used up the
chain of reactions continue
When substance C is not consumed
then its concentration can build up. Under these conditions substance C could bind to the allosteric site on the enzyme-1, causing the enzyme to change shape and be unable to bind to substrate.
When substance C again starts to be consumed
then the inhibitor that bound the enzyme will dissociate, and the enzyme will regain activity
back to outline
modulators of enzyme activity
noncompetitive enzyme inhibitor