Cyclic 3',5'AMP phosphodiesterase in Physarum polycephalum. II. Kinetic properties.

Some kinetic characteristics of soluble and particulate cyclic 3',5'-AMP phosphodiesterases from Physarum polycephalum are presented. The nature of enzyme inhibition by various agents is reported. The relationship between various enzyme inhibitors and their reported chemotactic properties in Physarum is examined. The results suggest that the chemoattractant effect of several inhibitors may be related to their ability to inhibit the particulate and extracellular phosphodiesterases, but is unrelated to inhibition of the intracellular enzyme.