Involvement of acetosyringone in plant–pathogen recognition

Abstract

In this study, acetosyringone was identified as one of the major extracellular phenolics in tobacco suspension cells and was shown to have bioactive properties that influence early events in plant-bacterial pathogenesis. In our model system, tobacco cell suspensions treated with bacterial isolate Pseudomonas syringae WT (HR+) undergo a resistant interaction characterized by a burst in oxygen uptake several hours after inoculation. When the extracellular concentration of acetosyringone in tobacco cell suspensions was supplemented with exogenous acetosyringone, the burst in oxygen uptake occurred as much as 1.5h earlier. The exogenous acetosyringone had no effect on tobacco suspensions undergoing susceptible interactions with Pseudomonas tabaci or a non-resistant interaction with a near-isogenic mutant derivative of isolate P. syringae WT (HR+). Resistant interactions with isolate P. syringae WT (HR+) also produce an oxidative burst which oxidizes the extracellular acetosyringone. This study demonstrates that acetosyringone, and likely other extracellular phenolics, may have bioactive characteristics that can influence plant-bacterial pathogenesis.

O-methyltransferase(s)-suppressed plants produce lower amounts of phenolic vir inducers and are less susceptible to Agrobacterium tumefaciens infection

“…repair in damaged cells or potentially toxic to other soil pathogens (Stachel et al 1985a). This last assertion is supported by the recent report of inhibitory effects of acetosyringone on Pseudomonas syringae virulence (Baker et al 2005) and aflatoxin biosynthetic genes of Aspergillus flavus (Hua et al 1999;Hua 2001). This suggests that Agrobacterium tumefaciens has evolved an acquired resistance to acetosyringone.…”

Effect of Acetosyringone on <i>Agrobacterium</i>-mediated Transformation of <i>Eustoma grandiflorum</i> Leaf Disks

“…AS induces the vir gene in the Ti plasmid of Agrobacterium and enhances infection (Baker et al 2005). AS is used for the transformation of monocots, such as Oryza sativa, which do not produce AS-like phenolic compounds (Hiei et al 1994).…”

New colorimetric screening assays for the directed evolution of fungal laccases to improve the conversion of plant biomass

“…In recent findings we have highlighted the biotechnological potential of fungal laccases and their natural redox mediators for improving the conversion of plant biomass in the modern integrated lignocellulose biorefinaries [10]. Moreover, sinapic acid, acetosyringone and other bioactive compounds with anti-bacterial and antioxidant properties [11,12] can be used to add new properties to cellulose or wood fibers by grafting reactions catalyzed by laccase [13]. Other phenolic compounds that can be extracted from wood lignin like syringaldehyde or vanillin provide flavor and fragrance or are used as chemical precursors for pharmaceuticals [14,15].…”