Figure 2. Bacterial CDNs and representative regulatory mechanisms.
Solid lines show direct binding or transport; dashed lines illustrate indirect effects. The prevalent distribution of c-di-GMP/cGAMP and c-di-AMP in Gram-negative and Gram-positive bacteria, respectively, is illustrated by differences in the cell envelope, with a thick peptidoglycan layer illustrating the Gram-positive cell wall. Abbreviations are as follows: T2SS - Type 2 secretion system; T4P - type 4 pili; LmPC - L. monocytogenes pyruvate carboxylase.