title: Characterization of an endosymbiont infecting wood ticks, Dermacentor andersoni, as a member of the genus Francisella.
abstract: A microorganism (Dermacantor andersoni symbiont [DAS]) infecting Rocky Mountain wood ticks (D. andersoni) collected in the Bitterroot Mountains of western Montana was characterized as an endosymbiont belonging to the genus Francisella. Previously described as Wolbachia like, the organism's DNA was amplified from both naturally infected tick ovarial tissues and Vero cell cultures by PCR assay with primer sets derived from eubacterial 16S ribosomal DNA (rDNA) and Francisella membrane protein genes. The 16S rDNA gene sequence of the DAS was most similar (95.4%) to that of Francisella tularensis subsp. tularensis. Through a combination of Giménez staining, PCR assay, and restriction fragment length polymorphism analysis, 102 of 108 female ticks collected from 1992 to 1996 were infected. Transovarial transmission to female progeny was 95.6%, but we found no evidence of horizontal transmission.
authors.affiliation: Laboratory of Microbial Structure and Function, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, USA. mark_niebylski@nih.gov
authors.forename: M L
authors.initials: ML
authors.lastname: Niebylski
authors.forename: M G
authors.initials: MG
authors.lastname: Peacock
authors.forename: E R
authors.initials: ER
authors.lastname: Fischer
authors.forename: S F
authors.initials: SF
authors.lastname: Porcella
authors.forename: T G
authors.initials: TG
authors.lastname: Schwan
mesh_terms: D000818:Animals; D001096:Arachnid Vectors / Q000382:microbiology* / Q000648:ultrastructure; D001483:Base Sequence; D002522:Chlorocebus aethiops; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D003870:Dermacentor / Q000382:microbiology* / Q000648:ultrastructure; D005260:Female; D005603:Francisella / Q000235:genetics / Q000302:isolation & purification* / Q000648:ultrastructure; D008854:Microscopy, Electron; D010053:Ovary / Q000382:microbiology; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D013559:Symbiosis; D014709:Vero Cells
chemical_list: D017931:DNA Primers; D004269:DNA, Bacterial; D004275:DNA, Ribosomal