Fig. 3.

Possible convergence of quorum sensing and cdiGMP signaling in the regulation of diverse bacterial behaviors. Cell density–dependent extracellular autoinducers activate membrane-bound (shown) or cytoplasmic sensory receptor proteins (not shown) which, through DNA binding proteins, regulate cellular processes including those listed. A variety of extracellular signals activate membrane-bound (shown) or cytoplasmic DGC and PDEA domain proteins (not shown), which synthesize and hydrolyze cdiGMP, respectively. cdiGMP functions as an activator or repressor of many of the same cellular processes regulated by quorum signaling (listed). Hypothetical connections between quorum-sensing and cdiGMP signaling are denoted by dashed lines.