An Adenosine 3′,5′-Monophosphate-dependent Protein Kinase from Escherichia coli

Abstract An enzyme present in Escherichia coli which catalyzes the phosphorylation of histone by ATP has been found to be stimulated by adenosine 3',5'-monophosphate (cyclic AMP). The rate of the enzyme-catalyzed phosphorylation of histone was increased by about 300% at concentrations of cyclic AMP above 7 x 10-7 m. The apparent Km of the E. coli enzyme for cyclic AMP was about 2 x 10-7 m.