Effect of Cyclic Guanosine 3′,5′-Monophosphate on the Synthesis of Enzymes Sensitive to Catabolite Repression in Intact Cells of Escherichia coli

Abstract

Cyclic guanosine 3′,5′-monophosphate inhibits the synthesis of β-galactosidase and tryptophanase in cultures of Escherichia coli growing in minimal media with glucose or glycerol as the carbon source. Cyclic guanosine 3′,5′-monophosphate acts at the transcriptional level in the lac operon, it exerts its action at the promoter site of the operon, and requires the presence of functional cyclic adenosine 3′,5′-monophosphate receptor protein.