... structural domains, while proCPY would be composed of a single fragile domain. The propeptide of the proenzymewould be located at the interface of the two domains thuscombining them into one body, ... sym-metrical single peak (Fig. 1A), indicating that the thermalunfolding process of the precursor form follows a two-statetransition. The ratio of the unfolding enthalpy (DHcal)tothevan’t Hoff enthalpy ... that the cleft of the active site will be located in the interface between the two structural domains of CPY and would be filled by the propeptide, thus uniting the two domains in a body, as ifthe...