(A) DGC proteins, (B) DGC-PDE proteins and PDE/HD-GYP only proteins. Atu gene numbers and if assigned, genetic names are provided for each protein. Predicted transmembrane domains are indicated by vertical lines and any recognizable functional domains are indicated. Protein domains. REC - two-component-type receiver domain; GAF - cGMP-specific phosphodiesterases, Adenylyl cyclases and FhlA; HAMP - Histidine kinases, Adenyl cyclases, Methyl-accepting proteins and Phosphatases; PAS - Per, ARNT, Sim; CBS - Cystathionine-Beta-Synthase; CHASE4, predicted ligand binding module; MHYT, 6-transmembrane domain; DISM, 7-transmembrane domain, Diverse Intracellular Signaling Modules.