title: Genome Sequencing and Transposon Mutagenesis of Burkholderia seminalis TC3.4.2R3 Identify Genes Contributing to Suppression of Orchid Necrosis Caused by B. gladioli.
abstract: From a screen of 36 plant-associated strains of Burkholderia spp., we identified 24 strains that suppressed leaf and pseudobulb necrosis of orchid caused by B. gladioli. To gain insights into the mechanisms of disease suppression, we generated a draft genome sequence from one suppressive strain, TC3.4.2R3. The genome is an estimated 7.67 megabases in size, with three replicons, two chromosomes, and the plasmid pC3. Using a combination of multilocus sequence analysis and phylogenomics, we identified TC3.4.2R3 as B. seminalis, a species within the Burkholderia cepacia complex that includes opportunistic human pathogens and environmental strains. We generated and screened a library of 3,840 transposon mutants of strain TC3.4.2R3 on orchid leaves to identify genes contributing to plant disease suppression. Twelve mutants deficient in suppression of leaf necrosis were selected and the transposon insertions were mapped to eight loci. One gene is in a wcb cluster that is related to synthesis of extracellular polysaccharide, a key determinant in bacterial-host interactions in other systems, and the other seven are highly conserved among Burkholderia spp. The fundamental information developed in this study will serve as a resource for future research aiming to identify mechanisms contributing to biological control.
authors.affiliation: 1 Laboratory of Molecular Biology and Microbial Ecology, Department of Microbiology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil;
authors.forename: Welington L
authors.initials: WL
authors.lastname: Araújo
authors.affiliation: 2 Department of Botany and Plant Pathology; and.|3 Molecular and Cellular Biology Program, Oregon State University, Corvallis, OR, U.S.A.;
authors.forename: Allison L
authors.initials: AL
authors.lastname: Creason
authors.affiliation: 1 Laboratory of Molecular Biology and Microbial Ecology, Department of Microbiology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil;
authors.forename: Emy T
authors.initials: ET
authors.lastname: Mano
authors.affiliation: 1 Laboratory of Molecular Biology and Microbial Ecology, Department of Microbiology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil;|4 Interdisciplinary Center for Biotechnology, University of Mogi das Cruzes, Mogi das Cruzes, Brazil;
authors.forename: Aline A
authors.initials: AA
authors.lastname: Camargo-Neves
authors.affiliation: 4 Interdisciplinary Center for Biotechnology, University of Mogi das Cruzes, Mogi das Cruzes, Brazil;
authors.forename: Sonia N
authors.initials: SN
authors.lastname: Minami
authors.affiliation: 2 Department of Botany and Plant Pathology; and.|3 Molecular and Cellular Biology Program, Oregon State University, Corvallis, OR, U.S.A.;|5 Center for Genome Research and Biocomputing, Oregon State University; and.
authors.forename: Jeff H
authors.initials: JH
authors.lastname: Chang
authors.affiliation: 2 Department of Botany and Plant Pathology; and.|3 Molecular and Cellular Biology Program, Oregon State University, Corvallis, OR, U.S.A.;|6 USDA-Agricultural Research Service, Horticultural Crops Laboratory, Corvallis, Oregon, U.S.A.
authors.forename: Joyce E
authors.initials: JE
authors.lastname: Loper
mesh_terms: D061046:Biological Control Agents; D019117:Burkholderia / Q000235:genetics* / Q000472:pathogenicity; D004251:DNA Transposable Elements; D005798:Genes, Bacterial; D016680:Genome, Bacterial; D054884:Host-Pathogen Interactions; D016296:Mutagenesis; D029595:Orchidaceae / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology; D018515:Plant Leaves / Q000382:microbiology*; D031786:Saccharum / Q000382:microbiology
chemical_list: D061046:Biological Control Agents; D004251:DNA Transposable Elements