title: Rickettsial relative associated with papaya bunchy top disease.
abstract: The phylogeny of a previously unidentified, obligate laticifer-inhabiting bacterium associated with the papaya bunchy top disease was investigated. Portions of genes corresponding to those for 16S rRNA, the flavoprotein subunit of succinate dehydrogenase (SdhA), citrate synthase (GltA), and the 17-kDa rickettsial common antigen were isolated and sequenced from the non-cultivable bacterium from diseased plants. Comparative sequence analyses consistently indicated that the bacterium is a member of the alpha-subdivision of the Proteobacteria and of the genus Rickettsia. The rickettsia was detected by polymerase chain reaction in diseased, but not healthy, papaya tissues and in the leafhopper vector, Empoasca papayae, providing further evidence of the possible etiological role of the bacterium in the disease. Although Rickettsia have been found naturally in arthropods and can be pathogenic to humans and other vertebrates, this is the first evidence of its kind implicating a Rickettsia as a plant pathogen.
authors.affiliation: Tropical Research and Education Center, University of Florida, 18905 SW 280 Street, Homestead, FL 33031, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Davis
authors.forename: Z
authors.initials: Z
authors.lastname: Ying
authors.forename: B R
authors.initials: BR
authors.lastname: Brunner
authors.forename: A
authors.initials: A
authors.lastname: Pantoja
authors.forename: F H
authors.initials: FH
authors.lastname: Ferwerda
mesh_terms: D002950:Citrate (si)-Synthase / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000209:etiology* / Q000382:microbiology*; D010936:Plant Extracts / Q000737:chemistry / Q000235:genetics; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012281:Rickettsia / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D012282:Rickettsia Infections / Q000150:complications*; D013385:Succinate Dehydrogenase / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D010936:Plant Extracts; D012336:RNA, Ribosomal, 16S; D013385:Succinate Dehydrogenase; D002950:Citrate (si)-Synthase