PecS is an important player in the regulatory network governing the coordinated expression of virulence genes during the interaction between Dickeya dadantii 3937 and plants

摘要: Summary Successful infection of a pathogen relies on the coordinated expression numerous virulence factor-encoding genes. In plant–bacteria interactions, this control is very often achieved through integration several regulatory circuits controlling cell–cell communication or sensing environmental conditions. Dickeya dadantii (formerly Erwinia chrysanthemi), causal agent soft rot many crops and ornamentals, provokes maceration infected plants mainly by producing secreting battery plant cell wall-degrading enzymes. However, other factors have also been characterized. During Arabidopsis infection, most D. dadantii gene transcripts accumulated in manner during infection. This activation requires functional GacA–GacS two-component system but Gac not involved growth phase dependence expression. Here we show that, contrary to Pectobacterium, AHL-mediated ExpIR quorum-sensing does play major role phase-dependent On hand, global regulator PecS participates since, pecS mutant, an early genes observed both vitro planta. correlated with known hypervirulence phenotype mutant. Analysis relationship between governed GacA regulators indicates that these two act independently. prevents premature first stages colonization whereas GacA, presumably conjunction regulators, required for at onset symptom occurrence.