Evidence for the Presence of CAMP, CAMP Receptor and Transcription Termination Factor Rho in Different Gram-negative Bacteria

Cyclic AMP has been shown to be present in 12 different Gram-negative bacteria and the regulation of its concentration, as a function of growth conditions, is similar to that described for Escherichia coli K12. Antibodies raised against catabolite activator protein (CAP) and Rho protein of E. coli K12 were used to check for the occurrence of cross-reactive antigens. Using radioimmunological assays, immunoblotting techniques and biochemical criteria we showed a wide distribution of CAP and Rho, structurally and functionally closely related to the corresponding E. coli K12 proteins. These results suggest that transcription is similarly regulated by these factors in Gram-negative bacteria.