Fig 6. C-di-GMP regulatory model in surface exposed E. amylovora cells.

Our study indicates that there is a dimorphism in the regulatory targets of the c-di-GMP generated by each of the five Edcs. While each Edc uniquely regulates the transcription of several genes, and virulence factors in vitro and in planta, attachment/biofilm formation (dependent on EPS production) is regulated by all the Edcs, thus, leading us to hypothesize about the potential presence of a localized and a diffused pool of c-di-GMP that can achieve these varied regulatory targets. Red inhibitor lines and green arrows indicate negative and positive regulation respectively, with arrow breaks indicating intermediate regulatory steps.