title: Methylobacterium-plant interaction genes regulated by plant exudate and quorum sensing molecules.
abstract: Bacteria from the genus Methylobacterium interact symbiotically (endophytically and epiphytically) with different plant species. These interactions can promote plant growth or induce systemic resistance, increasing plant fitness. The plant colonization is guided by molecular communication between bacteria-bacteria and bacteria-plants, where the bacteria recognize specific exuded compounds by other bacteria (e.g. homoserine molecules) and/or by the plant roots (e.g. flavonoids, ethanol and methanol), respectively. In this context, the aim of this study was to evaluate the effect of quorum sensing molecules (N-acyl-homoserine lactones) and plant exudates (including ethanol) in the expression of a series of bacterial genes involved in Methylobacterium-plant interaction. The selected genes are related to bacterial metabolism (mxaF), adaptation to stressful environment (crtI, phoU and sss), to interactions with plant metabolism compounds (acdS) and pathogenicity (patatin and phoU). Under in vitro conditions, our results showed the differential expression of some important genes related to metabolism, stress and pathogenesis, thereby AHL molecules up-regulate all tested genes, except phoU, while plant exudates induce only mxaF gene expression. In the presence of plant exudates there is a lower bacterial density (due the endophytic and epiphytic colonization), which produce less AHL, leading to down regulation of genes when compared to the control. Therefore, bacterial density, more than plant exudate, influences the expression of genes related to plant-bacteria interaction.
authors.affiliation: Departamento de Genética, Universidade de São Paulo, Piracicaba, SP, Brazil.
authors.forename: Manuella Nóbrega
authors.initials: MN
authors.lastname: Dourado
authors.affiliation: Departamento de Genética, Universidade de São Paulo, Piracicaba, SP, Brazil.
authors.forename: Andrea Cristina
authors.initials: AC
authors.lastname: Bogas
authors.affiliation: Departamento de Química, Universidade Estadual de Maringá, Maringá, PR, Brazil.
authors.forename: Armando M
authors.initials: AM
authors.lastname: Pomini
authors.affiliation: Departamento de Ciências do Solos, Escola Superior de Agricultura "Luiz de Queiróz", Universidade de São Paulo, Piracicaba, SP, Brazil.
authors.forename: Fernando Dini
authors.initials: FD
authors.lastname: Andreote
authors.affiliation: Departamento de Genética, Universidade de São Paulo, Piracicaba, SP, Brazil.
authors.forename: Maria Carolina
authors.initials: MC
authors.lastname: Quecine
authors.affiliation: Instituto de Química, Universidade de Campinas, Campinas, São Paulo, Brazil.
authors.forename: Anita J
authors.initials: AJ
authors.lastname: Marsaioli
authors.affiliation: Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Welington Luiz
authors.initials: WL
authors.lastname: Araújo
mesh_terms: D054742:Acyl-Butyrolactones / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects*; D006790:Host-Parasite Interactions; D020580:Methylobacterium / Q000254:growth & development / Q000502:physiology*; D010936:Plant Extracts / Q000378:metabolism*; D010944:Plants / Q000382:microbiology*
chemical_list: D054742:Acyl-Butyrolactones; D010936:Plant Extracts
keywords: Methylobacterium; endophyte; homoserine; plant-bacteria Interaction; quantitative PCR (qPCR)