Articles
CYCLIC DI-GMP REGULATES THE EXPRESSION OF VIRULENCE FACTORS IN ERWINIA AMYLOVORA
Article number
1056_32
Pages
199 – 205
Language
English
Abstract
Cyclic di-GMP (c-di-GMP), a secondary intracellular messenger molecule, is involved in the regulation of many cellular processes in numerous bacterial species, including the transition from a motile to sessile lifestyle, virulence, biosynthesis of exopolysaccharides and adhesion structures.
The cellular levels of this messenger compound are controlled by enzymatic synthesis and degradation, catalyzed by diguanylate cyclases and phosphodiesterases, respectively.
Signal transduction and phenotypic modulation is determined by binding of c-di-GMP to specific downstream receptors.
Although c-di-GMP has been shown to be an important intracellular signal in several plant pathogenic bacteria, the role of this molecule in Erwinia amylovora has not been previously investigated.
Using gene overexpression and site-directed mutagenesis analyses, we identified three active diguanylate cyclases (EdcA, EdcC and EdcE) in this bacterial pathogen.
Phenotypic analyses demonstrated that c-di-GMP positively regulates the biosynthesis of both cellulose and amylovoran, positively regulates biofilm formation, and represses motility.
Disease assays on immature pears and apple tree shoots demonstrated that c-di-GMP negatively regulates virulence in these infection models.
In addition, using a bioinformatic approach, a candidate c-di-GMP receptor protein, EAM_3387, was predicted.
These results demonstrated that c-di-GMP is a key component of the regulatory networks that govern the expression of virulence traits in E. amylovora.
The cellular levels of this messenger compound are controlled by enzymatic synthesis and degradation, catalyzed by diguanylate cyclases and phosphodiesterases, respectively.
Signal transduction and phenotypic modulation is determined by binding of c-di-GMP to specific downstream receptors.
Although c-di-GMP has been shown to be an important intracellular signal in several plant pathogenic bacteria, the role of this molecule in Erwinia amylovora has not been previously investigated.
Using gene overexpression and site-directed mutagenesis analyses, we identified three active diguanylate cyclases (EdcA, EdcC and EdcE) in this bacterial pathogen.
Phenotypic analyses demonstrated that c-di-GMP positively regulates the biosynthesis of both cellulose and amylovoran, positively regulates biofilm formation, and represses motility.
Disease assays on immature pears and apple tree shoots demonstrated that c-di-GMP negatively regulates virulence in these infection models.
In addition, using a bioinformatic approach, a candidate c-di-GMP receptor protein, EAM_3387, was predicted.
These results demonstrated that c-di-GMP is a key component of the regulatory networks that govern the expression of virulence traits in E. amylovora.
Publication
Authors
L.F. Castiblanco, A.C. Edmunds, C.M. Waters, G.W. Sundin
Keywords
Erwinia amylovora, cyclic di-GMP, intracellular signaling molecule
Online Articles (52)