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Journal of Clinical Microbiology logoLink to Journal of Clinical Microbiology
. 1996 Jun;34(6):1526–1530. doi: 10.1128/jcm.34.6.1526-1530.1996

Genetic variation in Australian spotted fever group rickettsiae.

R W Baird 1, J Stenos 1, R Stewart 1, B Hudson 1, M Lloyd 1, S Aiuto 1, B Dwyer 1
PMCID: PMC229054  PMID: 8735110

Abstract

Rickettsiae were isolated by cell culture of buffy coat blood from six patients with spotted fever from southeastern Australia and Flinders Island in Bass Strait. The isolates were genetically compared with two previous Rickettsia australis patient isolates. The genus-specific 17-kDA genes from the isolates were compared after DNA amplification and restriction fragment analysis of the amplified DNA. This comparison revealed that mainland rickettsial isolates from southeastern Australia were identical to two previous isolates of R. australis from northeastern Australia. Rickettsial isolates from Flinders Island were distinct from the mainland isolates. The 16S rRNA gene sequences from the isolates were determined and compared. The Flinders Island rickettsial agent was most closely related (0.3% structural divergence) to Rickettsia rickettsii, Rickettsia conorii, and Rickettsia slovaca. The Flinders Island rickettsial agent was 1.3 and 2.1% structurally divergent from R. australis and Rickettsia akari, respectively. The 16S rRNA gene sequence from the Flinders Island agent shows that this rickettsia is more closely related to the rickettsial spotted fever group than is R. australis. We conclude that there are two populations of spotted fever group rickettsiae in Australia and propose that the genetically distinct causative organism of Flinders Island spotted fever be designated Rickettsia honei. The extent of distribution and animal host reservoirs remain to be elucidated.

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Selected References

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  1. Anderson B. E., Tzianabos T. Comparative sequence analysis of a genus-common rickettsial antigen gene. J Bacteriol. 1989 Sep;171(9):5199–5201. doi: 10.1128/jb.171.9.5199-5201.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Baird R. W., Lloyd M., Stenos J., Ross B. C., Stewart R. S., Dwyer B. Characterization and comparison of Australian human spotted fever group rickettsiae. J Clin Microbiol. 1992 Nov;30(11):2896–2902. doi: 10.1128/jcm.30.11.2896-2902.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Balayeva N. M., Eremeeva M. E., Raoult D. Genomic identification of Rickettsia slovaca among spotted fever group rickettsia isolates from Dermacentor marginatus in Armenia. Acta Virol. 1994 Dec;38(6):321–325. [PubMed] [Google Scholar]
  4. Dwyer B. W., Graves S. R., McDonald M. I., Yung A. P., Doherty R. R., McDonald J. K. Spotted fever in East Gippsland, Victoria: a previously unrecognised focus of rickettsial infection. Med J Aust. 1991 Jan 21;154(2):121–125. doi: 10.5694/j.1326-5377.1991.tb120998.x. [DOI] [PubMed] [Google Scholar]
  5. Eremeeva M., Yu X., Raoult D. Differentiation among spotted fever group rickettsiae species by analysis of restriction fragment length polymorphism of PCR-amplified DNA. J Clin Microbiol. 1994 Mar;32(3):803–810. doi: 10.1128/jcm.32.3.803-810.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Graves S. R., Dwyer B. W., McColl D., McDade J. E. Flinders Island spotted fever: a newly recognised endemic focus of tick typhus in Bass Strait. Part 2. Serological investigations. Med J Aust. 1991 Jan 21;154(2):99–104. doi: 10.5694/j.1326-5377.1991.tb120994.x. [DOI] [PubMed] [Google Scholar]
  7. Jackson K., Sievers A., Ross B. C., Dwyer B. Isolation of a fastidious Mycobacterium species from two AIDS patients. J Clin Microbiol. 1992 Nov;30(11):2934–2937. doi: 10.1128/jcm.30.11.2934-2937.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. POPE J. H. The isolation of a rickettsia resembling Rickettsia australis in South East Queensland. Med J Aust. 1955 May 21;42(1 21):761–763. [PubMed] [Google Scholar]
  9. Rogall T., Wolters J., Flohr T., Böttger E. C. Towards a phylogeny and definition of species at the molecular level within the genus Mycobacterium. Int J Syst Bacteriol. 1990 Oct;40(4):323–330. doi: 10.1099/00207713-40-4-323. [DOI] [PubMed] [Google Scholar]
  10. Roux V., Raoult D. Phylogenetic analysis of the genus Rickettsia by 16S rDNA sequencing. Res Microbiol. 1995 Jun;146(5):385–396. doi: 10.1016/0923-2508(96)80284-1. [DOI] [PubMed] [Google Scholar]
  11. Sexton D. J., Dwyer B., Kemp R., Graves S. Spotted fever group rickettsial infections in Australia. Rev Infect Dis. 1991 Sep-Oct;13(5):876–886. doi: 10.1093/clinids/13.5.876. [DOI] [PubMed] [Google Scholar]
  12. Stenos J., Graves S., Dwyer B. Quantification of Rickettsia australis. Am J Trop Med Hyg. 1992 Aug;47(2):141–146. doi: 10.4269/ajtmh.1992.47.141. [DOI] [PubMed] [Google Scholar]
  13. Stewart R. S. Flinders Island spotted fever: a newly recognised endemic focus of tick typhus in Bass Strait. Part 1. Clinical and epidemiological features. Med J Aust. 1991 Jan 21;154(2):94–99. doi: 10.5694/j.1326-5377.1991.tb120993.x. [DOI] [PubMed] [Google Scholar]
  14. Stothard D. R., Clark J. B., Fuerst P. A. Ancestral divergence of Rickettsia bellii from the spotted fever and typhus groups of Rickettsia and antiquity of the genus Rickettsia. Int J Syst Bacteriol. 1994 Oct;44(4):798–804. doi: 10.1099/00207713-44-4-798. [DOI] [PubMed] [Google Scholar]

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