title: Plants genetically modified to produce N-acylhomoserine lactones communicate with bacteria.
abstract: N-acylhomoserine lactones (AHLs) play a critical role in plant/microbe interactions. The AHL, N-(3-oxohexanoyl)-L-homoserine lactone (OHHL), induces exoenzymes that degrade the plant cell wall by the pathogenic bacterium Erwinia carotovora. Conversely, the antifungal activity of the biocontrol bacterium Pseudomonas aureofaciens 30-84 is due (at least in part) to phenazine antibiotics whose synthesis is regulated by N-hexanoylhomoserine lactone (HHL). Targeting the product of an AHL synthase gene (yenI) from Yersinia enterocolitica to the chloroplasts of transgenic tobacco plants caused the synthesis in plants of the cognate AHL signaling molecules (OHHL and HHL). The AHLs produced by the transgenic plants were sufficient to induce target gene expression in several recombinant bacterial AHL biosensors and to restore biocontrol activity to an HHL-deficient P. aureofaciens strain. In addition, pathogenicity was restored to an E. carotovora strain rendered avirulent as a consequence of a mutation in the OHHL synthase gene, carI. The ability to generate bacterial quorum-sensing signaling molecules in the plant offers novel opportunities for disease control and for manipulating plant/microbe interactions.
authors.affiliation: School of Biological Sciences, Nottingham University, Loughborough LE12 5RD, UK. rupert.fray@nottingham.ac.uk
authors.forename: R G
authors.initials: RG
authors.lastname: Fray
authors.forename: J P
authors.initials: JP
authors.lastname: Throup
authors.forename: M
authors.initials: M
authors.lastname: Daykin
authors.forename: A
authors.initials: A
authors.lastname: Wallace
authors.forename: P
authors.initials: P
authors.lastname: Williams
authors.forename: G S
authors.initials: GS
authors.lastname: Stewart
authors.forename: D
authors.initials: D
authors.lastname: Grierson
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D005818:Genetic Engineering; D007783:Lactones / Q000378:metabolism*; D016973:Pectobacterium carotovorum / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000382:microbiology*; D015398:Signal Transduction; D015534:Trans-Activators / Q000235:genetics; D015008:Yersinia enterocolitica / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D007783:Lactones; D015534:Trans-Activators; C096956:yenI protein, Yersinia enterocolitica