A PilZ domain protein for chemotaxis adds another layer to c-di-GMP–mediated regulation of flagellar motility

Cyclic diguanylate monophosphate (c-di-GMP) is a ubiquitous second messenger in bacteria. In this issue of Science Signaling, Xu et al show that c-di-GMP regulates chemotaxis by binding to the PilZ domain protein MapZ to alter the methyltransferase activity of its protein partner CheR, fleshing out the c-di-GMP signaling network of the opportunistic pathogen Pseudomonas aeruginosa.