title: ABrucellaspp. Isolate from a Pac-Man Frog (Ceratophrys ornata) Reveals Characteristics Departing from Classical Brucellae.
abstract: Brucellaare highly infectious bacterial pathogens responsible for brucellosis, a frequent worldwide zoonosis. TheBrucellagenus has recently expanded from 6 to 11 species, all of which were associated with mammals; The natural host range recently expanded to amphibians after some reports of atypical strains from frogs. Here we describe the first in depth phenotypic and genetic characterization of aBrucellastrains isolated from a frog. Strain B13-0095 was isolated from a Pac-Man frog (Ceratophyrus ornate) at a veterinary hospital in Texas and was initially misidentified asOchrobactrum anthropi. We found that B13-0095 belongs to a group of early-diverging brucellae that includesBrucella inopinatastrain BO1 and theB. inopinata-like strain BO2, with traits that depart significantly from those of the "classical"Brucellaspp. Analysis of B13-0095 genome sequence revealed several specific features that suggest that this isolate represents an intermediate between a soil associated ancestor and the host adapted "classical" species. Like strain BO2, B13-0095 does not possess the genes required to produce the perosamine based LPS found in classicalBrucella, but has a set of genes that could encode a rhamnose based O-antigen. Despite this, B13-0095 has a very fast intracellular replication rate in both epithelial cells and macrophages. Finally, another major finding in this study is the bacterial motility observed for strains B13-0095, BO1, and BO2, which is remarkable for this bacterial genus. This study thus highlights several novel characteristics in strains belonging to an emerging group within theBrucellagenus. Accurate identification tools for such atypicalBrucellaisolates and careful evaluation of their zoonotic potential, are urgently required.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, U1047, UFR de MédecineNîmes, France; Université de Montpellier, U1047Nîmes, France.
authors.forename: Pedro F
authors.initials: PF
authors.lastname: Soler-Lloréns
authors.affiliation: Mycobacteria and Brucella Section, National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, United States Department of Agriculture Ames, IA, USA.
authors.forename: Chris R
authors.initials: CR
authors.lastname: Quance
authors.affiliation: Clinical Microbiology, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Science, Texas A&M University College Station, TX, USA.
authors.forename: Sara D
authors.initials: SD
authors.lastname: Lawhon
authors.affiliation: Mycobacteria and Brucella Section, National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, United States Department of Agriculture Ames, IA, USA.
authors.forename: Tod P
authors.initials: TP
authors.lastname: Stuber
authors.affiliation: Clinical Microbiology, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Science, Texas A&M University College Station, TX, USA.
authors.forename: John F
authors.initials: JF
authors.lastname: Edwards
authors.affiliation: Department of Veterinary Pathobiology, Texas A&M University College Station, TX, USA.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Ficht
authors.affiliation: Mycobacteria and Brucella Section, National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, United States Department of Agriculture Ames, IA, USA.
authors.forename: Suelee
authors.initials: S
authors.lastname: Robbe-Austerman
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, U1047, UFR de MédecineNîmes, France; Université de Montpellier, U1047Nîmes, France.
authors.forename: David
authors.initials: D
authors.lastname: O'Callaghan
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, U1047, UFR de MédecineNîmes, France; Université de Montpellier, U1047Nîmes, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Keriel
mesh_terms: D000818:Animals; D001001:Anura / Q000382:microbiology*; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D005075:Biological Evolution; D002002:Brucella / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D002006:Brucellosis / Q000382:microbiology* / Q000401:mortality; D002244:Carbon / Q000378:metabolism; D002460:Cell Line / Q000473:pathology; D002648:Child; D004269:DNA, Bacterial / Q000235:genetics; D004847:Epithelial Cells / Q000382:microbiology; D005260:Female; D005798:Genes, Bacterial; D016680:Genome, Bacterial; D006367:HeLa Cells / Q000473:pathology; D006801:Humans; D008070:Lipopolysaccharides / Q000145:classification / Q000235:genetics; D008264:Macrophages / Q000382:microbiology; D051379:Mice; D005810:Multigene Family; D019081:O Antigens / Q000235:genetics; D010641:Phenotype; D010802:Phylogeny; D012210:Rhamnose / Q000378:metabolism; D013781:Texas; D014774:Virulence; D015047:Zoonoses / Q000382:microbiology
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D008070:Lipopolysaccharides; D019081:O Antigens; D002244:Carbon; D012210:Rhamnose
keywords: Brucella; LPS; Ochrobactrum; evolution; frog; metabolism; motility; virulence