Allosteric enzyme | definition of allosteric enzyme by Medical dictionary
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an enzyme that exhibits the property of allosterism.
An enzyme whose activity can change when certain types of effectors, called allosteric effectors, bind to a nonactive site on the enzyme.
Fig. 25 Allosteric enzyme . Active (a) and inactive (b) forms.
allosteric enzyme a type of enzyme which has two alternative forms: one active with a functional BINDING SITE, the other inactive where the binding site has been altered in shape so as to become non-reactive. Such enzymes have a QUATERNARY PROTEIN STRUCTURE which becomes changed by the addition of a ‘modulator’ molecule producing the inactive shape, such a process resulting in NONCOMPETITIVE INHIBITION.