Interaction between the @S06083@ binding sites of an @A00240@. Binding of a substrate molecule to one @B00649@ changes the affinity of the binding sites on the other subunits (cf. @A00240@) to the substrate by induction of a @C01258@ change at the other binding sites. Cooperative @E02159@ typically display a sigmoid (S-shaped) plot of the reaction rate against substrate concentration.