Stability in vitro of uridine diphosphoglucose pyrophosphorylase in Dictyostelium discoideum.

The stability of uridine diphosphoglucose pyrophosphorylase was examined in extracts prepared at different stages of development in Dictyostelium discoideum. In the early stages, the kinetics of inactivation were nonlinear, and, therefore, it was not possible to determine the specific enzyme activity. In the later stages of development, the enzyme was stable, but it could be rapidly inactivated by a heat-labile inhibitor present in extracts prepared at an early stage.