Fig. 2.

Biofilm dispersion c-di-GMP signaling in P. aeruginosa Dispersion triggers such as NO, increased glutamate concentrations and HgCl₂ are sensed by the chemotaxis sensor BdlA. BdlA then activates the PDEs DipA and RbdA. In addition, NO increases the production of the PDE NbdA. These PDEs hydrolyze c-di-GMP resulting in a decrease of the c-di-GMP concentration. Consequently, c-di-GMP dissociates from LapD, which results in the release of the periplasmatic proteinase LapG. LapG then cleaves the Psl-bound CdrA and the surface-bound LapA, resulting in biofilm dispersion. The decrease of the c-di-GMP concentration also results in an increased production of matrix degrading enzymes such as the endonuclease EndA. The secreted matrix degrading enzymes consume the matrix components, causing cells to disperse from the biofilm. Black arrows indicate direct links, gray dashed arrows are partly unknown links.