title: Evidence for cyclic Di-GMP-mediated signaling in Bacillus subtilis.
abstract: Cyclic di-GMP (c-di-GMP) is a second messenger that regulates diverse cellular processes in bacteria, including motility, biofilm formation, cell-cell signaling, and host colonization. Studies of c-di-GMP signaling have chiefly focused on Gram-negative bacteria. Here, we investigated c-di-GMP signaling in the Gram-positive bacterium Bacillus subtilis by constructing deletion mutations in genes predicted to be involved in the synthesis, breakdown, or response to the second messenger. We found that a putative c-di-GMP-degrading phosphodiesterase, YuxH, and a putative c-di-GMP receptor, YpfA, had strong influences on motility and that these effects depended on sequences similar to canonical EAL and RxxxR-D/NxSxxG motifs, respectively. Evidence indicates that YpfA inhibits motility by interacting with the flagellar motor protein MotA and that yuxH is under the negative control of the master regulator Spo0A∼P. Based on these findings, we propose that YpfA inhibits motility in response to rising levels of c-di-GMP during entry into stationary phase due to the downregulation of yuxH by Spo0A∼P. We also present evidence that YpfA has a mild influence on biofilm formation. In toto, our results demonstrate the existence of a functional c-di-GMP signaling system in B. subtilis that directly inhibits motility and directly or indirectly influences biofilm formation.
authors: Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts, USA.
authors: Yun
authors: Y
authors: Chen
authors: Yunrong
authors: Y
authors: Chai
authors: Jian-hua
authors: JH
authors: Guo
authors: Richard
authors: R
authors: Losick
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018441:Biofilms / Q000254:growth & development; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000378:metabolism; D017353:Gene Deletion; D005798:Genes, Bacterial; D008124:Locomotion; D015398:Signal Transduction
chemical_list: C062025:bis(3',5')-cyclic diguanylic acid; D006152:Cyclic GMP