title: Evidence for an Opportunistic and Endophytic Lifestyle of the Bursaphelenchus xylophilus-Associated Bacteria Serratia marcescens PWN146 Isolated from Wilting Pinus pinaster.
abstract: Pine wilt disease (PWD) results from the interaction of three elements: the pathogenic nematode, Bursaphelenchus xylophilus; the insect-vector, Monochamus sp.; and the host tree, mostly Pinus species. Bacteria isolated from B. xylophilus may be a fourth element in this complex disease. However, the precise role of bacteria in this interaction is unclear as both plant-beneficial and as plant-pathogenic bacteria may be associated with PWD. Using whole genome sequencing and phenotypic characterization, we were able to investigate in more detail the genetic repertoire of Serratia marcescens PWN146, a bacterium associated with B. xylophilus. We show clear evidence that S. marcescens PWN146 is able to withstand and colonize the plant environment, without having any deleterious effects towards a susceptible host (Pinus thunbergii), B. xylophilus nor to the nematode model C. elegans. This bacterium is able to tolerate growth in presence of xenobiotic/organic compounds, and use phenylacetic acid as carbon source. Furthermore, we present a detailed list of S. marcescens PWN146 potentials to interfere with plant metabolism via hormonal pathways and/or nutritional acquisition, and to be competitive against other bacteria and/or fungi in terms of resource acquisition or production of antimicrobial compounds. Further investigation is required to understand the role of bacteria in PWD. We have now reinforced the theory that B. xylophilus-associated bacteria may have a plant origin.
authors.affiliation: NemaLab/ICAAM-Institute of Mediterranean Agricultural and Environmental Sciences, Biology Department, University of Évora, Évora, Portugal. cvicente@uevora.pt.|Department of Environmental Biology, Chubu University, Kasugai, Japan. cvicente@uevora.pt.
authors.forename: Cláudia S L
authors.initials: CS
authors.lastname: Vicente
authors.affiliation: NemaLab/ICAAM-Institute of Mediterranean Agricultural and Environmental Sciences, Biology Department, University of Évora, Évora, Portugal.|Departamento de Microbiologia, Laboratório de Microbiologia do Solo, Universidade Federal de Santa Catarina, Florianópolis, Brazil.
authors.forename: Francisco X
authors.initials: FX
authors.lastname: Nascimento
authors.affiliation: NemaLab/ICAAM-Institute of Mediterranean Agricultural and Environmental Sciences, Biology Department, University of Évora, Évora, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Barbosa
authors.affiliation: Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.|Ph.D. Program in Microbial Genomics, National Chung Hsing University and Academia Sinica, Taichung, Taiwan.
authors.forename: Huei-Mien
authors.initials: HM
authors.lastname: Ke
authors.affiliation: Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.
authors.forename: Isheng J
authors.initials: IJ
authors.lastname: Tsai
authors.affiliation: Forest Tree Breeding Center, Forestry and Forest Products Research Institute, Ibaraki, Japan.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Hirao
authors.affiliation: Information and Computer Sciences group, The James Hutton Institute, Invergowrie, DD2 5DA, Dundee, UK.
authors.forename: Peter J A
authors.initials: PJ
authors.lastname: Cock
authors.affiliation: Division of Parasitology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
authors.forename: Taisei
authors.initials: T
authors.lastname: Kikuchi
authors.affiliation: Department of Environmental Biology, Chubu University, Kasugai, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Hasegawa
authors.affiliation: NemaLab/ICAAM-Institute of Mediterranean Agricultural and Environmental Sciences, Biology Department, University of Évora, Évora, Portugal.|Departamento de Ciências da Vida, Universidade Lusófona de Humanidades e Tecnologias, Lisbon, Portugal.
authors.forename: Manuel
authors.initials: M
authors.lastname: Mota
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents; D000969:Antinematodal Agents / Q000494:pharmacology; D001483:Base Sequence; D002965:Classification; D001517:Coleoptera / Q000382:microbiology; D004269:DNA, Bacterial; D060026:Endophytes; D005798:Genes, Bacterial; D006790:Host-Parasite Interactions / Q000502:physiology; D007303:Insect Vectors / Q000382:microbiology; D008019:Life Style; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D058977:Molecular Sequence Annotation; D009348:Nematoda / Q000472:pathogenicity; D009894:Opportunistic Infections; D010802:Phylogeny; D028223:Pinus / Q000382:microbiology* / Q000469:parasitology; D010935:Plant Diseases / Q000382:microbiology; D012706:Serratia marcescens / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity* / Q000502:physiology*; D014197:Trees / Q000382:microbiology / Q000469:parasitology; D017187:Tylenchida / Q000187:drug effects / Q000382:microbiology* / Q000472:pathogenicity
chemical_list: D000890:Anti-Infective Agents; D000969:Antinematodal Agents; D004269:DNA, Bacterial
keywords: Bursaphelenchus xylophilus; Endophyte; Nematode; Pine wilt disease; Serratia marcescens