CYCLIC ADENOSINE-3',5'-MONOPHOSPHATE PHOSPHODIESTERASE FROM MUCOR-ROUXII - REGULATION OF ENZYME-ACTIVITY BY PHOSPHORYLATION AND DEPHOSPHORYLATION

Crude preparations of cyclic adenosine 3′, 5′-monophosphate phosphodiesterase were activated 1.5 to 2 fold by incubation with ATP, Mg2+ and cyclic AMP in a reaction which was both, time and temperature dependent. Cyclic AMP phosphodiesterase remained in an activated state upon filtration of the enzymatic preparation through Sephadex G-25 and ion-exchange chromatography. Activation of the enzyme in the presence of [γ 32P]ATP resulted in a significant amount of [32P] protein-bound radioactivity. Reversible deactivation of cyclic AMP phosphodiesterase was enhanced by Mg2+ and was accompanied by the release of [32P] protein bound radioactivity. The evidence is consistent with a mechanism for controlling cyclic AMP phosphodiesterase through phosphorylation-dephosphorylation sequence. © 1979.