title: Genome Report: Identification and Validation of Antigenic Proteins fromPajaroellobacter abortibovisUsingDe NovoGenome Sequence Assembly and Reverse Vaccinology.
abstract: Epizootic bovine abortion (EBA), or "foothill abortion," is the leading cause of beef cattle abortion in California and has also been reported in Nevada and Oregon. In the 1970s, the soft-shelled tickOrnithodoros coriaceus, or "pajaroello tick," was confirmed as the disease-transmitting vector. In 2005, a novel Deltaproteobacterium was discovered as the etiologic agent of EBA (aoEBA), recently namedPajaroellobacter abortibovisThis organism cannot be grown in culture using traditional microbiological techniques; it can only be grown in experimentally-infected severe combined immunodeficient (SCID) mice. The objectives of this study were to perform ade novogenome assembly forP. abortibovisand identify and validate potential antigenic proteins as candidates for future recombinant vaccine development. DNA and RNA were extracted from spleen tissue collected from experimentally-infected SCID mice following exposure toP. abortibovisThis combination of mouse and bacterial DNA was sequenced and aligned to the mouse genome. Mouse sequences were subtracted from the sequence pool and the remaining sequences werede novoassembled at 50x coverage into a 1.82 Mbp complete closed circular Deltaproteobacterial genome containing 2250 putative protein-coding sequences. Phylogenetic analysis ofP. abortibovispredicts that this bacterium is most closely related to the organisms of the order Myxococcales, referred to as Myxobacteria.In silicoprediction of vaccine candidates was performed using a reverse vaccinology approach resulting in the identification and ranking of the top 10 candidate proteins that are likely to be antigenic. Immunologic testing of these candidate proteins confirmed antigenicity of seven of the nine expressed protein candidates using serum fromP. abortibovisimmunized mice.
authors.affiliation: Department of Animal Science, University of California, Davis, California 95616.
authors.forename: Bryan T
authors.identifier: 0000-0002-4282-9285
authors.initials: BT
authors.lastname: Welly
authors.affiliation: Department of Animal Science, University of California, Davis, California 95616.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Miller
authors.affiliation: Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California 95616.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Stott
authors.affiliation: Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California 95616.
authors.forename: Myra T
authors.initials: MT
authors.lastname: Blanchard
authors.affiliation: Department of Animal Science, University of California, Davis, California 95616.
authors.forename: Alma D
authors.initials: AD
authors.lastname: Islas-Trejo
authors.affiliation: Department of Animal Science, University of California, Davis, California 95616.
authors.forename: Sean M
authors.initials: SM
authors.lastname: O'Rourke
authors.affiliation: Department of Animal Science, University of California, Davis, California 95616.
authors.forename: Amy E
authors.identifier: 0000-0002-4181-4233
authors.initials: AE
authors.lastname: Young
authors.affiliation: Department of Animal Science, University of California, Davis, California 95616.
authors.forename: Juan F
authors.identifier: 0000-0001-7113-3183
authors.initials: JF
authors.lastname: Medrano
authors.affiliation: Department of Animal Science, University of California, Davis, California 95616 alvaneenennaam@ucdavis.edu.
authors.forename: Alison L
authors.identifier: 0000-0003-1562-162X
authors.initials: AL
authors.lastname: Van Eenennaam
mesh_terms: D000034:Abortion, Veterinary / Q000235:genetics* / Q000276:immunology / Q000382:microbiology* / Q000517:prevention & control; D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics* / Q000302:isolation & purification; D002140:California; D002417:Cattle; D020564:Deltaproteobacteria / Q000235:genetics / Q000276:immunology / Q000472:pathogenicity; D005260:Female; D016680:Genome, Bacterial; D059014:High-Throughput Nucleotide Sequencing; D051379:Mice; D016513:Mice, SCID / Q000276:immunology / Q000382:microbiology; D009231:Myxococcales / Q000235:genetics* / Q000276:immunology; D010802:Phylogeny; D011247:Pregnancy; D014611:Vaccination
chemical_list: D000942:Antigens, Bacterial
keywords: Ornithodoros coriaceus; Pajaroellobacter abortibovis; epizootic bovine abortion; recombinant vaccine; reverse vaccinology