title: Plant-associated symbiotic Burkholderia species lack hallmark strategies required in mammalian pathogenesis.
abstract: Burkholderia is a diverse and dynamic genus, containing pathogenic species as well as species that form complex interactions with plants. Pathogenic strains, such as B. pseudomallei and B. mallei, can cause serious disease in mammals, while other Burkholderia strains are opportunistic pathogens, infecting humans or animals with a compromised immune system. Although some of the opportunistic Burkholderia pathogens are known to promote plant growth and even fix nitrogen, the risk of infection to infants, the elderly, and people who are immunocompromised has not only resulted in a restriction on their use, but has also limited the application of non-pathogenic, symbiotic species, several of which nodulate legume roots or have positive effects on plant growth. However, recent phylogenetic analyses have demonstrated that Burkholderia species separate into distinct lineages, suggesting the possibility for safe use of certain symbiotic species in agricultural contexts. A number of environmental strains that promote plant growth or degrade xenobiotics are also included in the symbiotic lineage. Many of these species have the potential to enhance agriculture in areas where fertilizers are not readily available and may serve in the future as inocula for crops growing in soils impacted by climate change. Here we address the pathogenic potential of several of the symbiotic Burkholderia strains using bioinformatics and functional tests. A series of infection experiments using Caenorhabditis elegans and HeLa cells, as well as genomic characterization of pathogenic loci, show that the risk of opportunistic infection by symbiotic strains such as B. tuberum is extremely low.
authors.affiliation: Dept. of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Annette A
authors.initials: AA
authors.lastname: Angus
authors.affiliation: Dept. of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Christina M
authors.initials: CM
authors.lastname: Agapakis
authors.affiliation: Dept. of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Fong
authors.affiliation: Baylor College of Medicine, Houston, Texas, United States of America.
authors.forename: Shailaja
authors.initials: S
authors.lastname: Yerrapragada
authors.affiliation: Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala, Ciudad de México, Distrito Federal, México.
authors.forename: Paulina
authors.initials: P
authors.lastname: Estrada-de los Santos
authors.affiliation: Dept. of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Paul
authors.initials: P
authors.lastname: Yang
authors.affiliation: Dept. of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Nannie
authors.initials: N
authors.lastname: Song
authors.affiliation: Dept. of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Kano
authors.affiliation: Genomic Sciences Center, National Autonomous University of México, Cuernavaca, Morelos, México.
authors.forename: Jésus
authors.initials: J
authors.lastname: Caballero-Mellado
authors.affiliation: Embrapa Agrobiologia, Seropédica, Rio de Janeiro, Brazil.
authors.forename: Sergio M
authors.initials: SM
authors.lastname: de Faria
authors.affiliation: Chemistry Department, Tshwane University of Technology, Arcadia Campus, Pretoria, South Africa.
authors.forename: Felix D
authors.initials: FD
authors.lastname: Dakora
authors.affiliation: Dept. of Genetics, Washington Univ. School of Medicine, St. Louis, Missouri, United States of America.
authors.forename: George
authors.initials: G
authors.lastname: Weinstock
authors.affiliation: Dept. of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California, United States of America ; Molecular Biology Institute, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Ann M
authors.initials: AM
authors.lastname: Hirsch
mesh_terms: D000818:Animals; D058947:Bacterial Secretion Systems / Q000235:genetics; D019117:Burkholderia / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D019121:Burkholderia Infections / Q000382:microbiology*; D017173:Caenorhabditis elegans / Q000382:microbiology; D004352:Drug Resistance, Microbial / Q000235:genetics; D005407:Flagella / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics; D056426:Genetic Loci; D006367:HeLa Cells; D006801:Humans; D008322:Mammals / Q000382:microbiology*; D005810:Multigene Family; D010802:Phylogeny; D010944:Plants / Q000382:microbiology*; D013559:Symbiosis / Q000235:genetics; D014774:Virulence / Q000235:genetics
chemical_list: D058947:Bacterial Secretion Systems