Skip directly to site content Skip directly to page options Skip directly to A-Z link Skip directly to A-Z link Skip directly to A-Z link
Volume 6, Number 4—August 2000
Letter

Phylogenetic Analysis of the Chinese Rickettsia Isolate BJ-90

Cite This Article

To the Editor: Five species of tick-associated rickettsiae have been identified in China; of these, three are human pathogens and two are of unknown pathogenicity (1). In 1990, one isolate, BJ-90, was first obtained from a Dermacentor sinicus tick, a newly recognized vector collected in a Beijing suburb, an atypical location for Rickettsia sibirica (2). Several taxonomic studies of the phenotype, antigenicity, and genotype of BJ-90 have been performed, with inconsistent results (2-6). Recently, phylogenetic analysis based on several gene comparisons has enabled the phylogenetic classification of this rickettsial species (7-11). To confirm the phylogenetic relationships between the BJ-90 strain and other rickettsiae, the 16S rRNA, gltA, and OmpA encoding genes were amplified and sequenced. Phylogenetic relationships between the BJ-90 strain and other rickettsia in the GenBank database were inferred by the parsimony and neighbor-joining methods (9). Bootstrap analyses were used to assess the reliability of the phylogenetic analysis.

Both methods showed a high degree of similarity between BJ-90, R. sibirica and R. mongolotimonae, which were grouped in the same cluster in three inferred dendrograms. The data from the 16S rRNA and gltA sequences showed low statistical significance in the cluster (bootstrap values for the nodes 50% and 33%, respectively). However, data from the rompA gene sequence showed highly significant similarity in the cluster (bootstrap value 100%), confirming the reliability of the phylogenetic analysis. The results of this phylogenetic analysis are consistent with those of previous phenotypic, genotypic, and phylogenetic analyses (2,3,5-11), as well as taxonomy derived from direct antigenic comparison of the species (4). The sequences of 16S rRNA, gltA, and OmpA have been assigned the following GenBank accession numbers: AF178036 for 16S rRNA, AF178035 for gltA, AF179365 for the 611-bp sequence of ompA, and AF179367 for the 3174-bp sequence of ompA. According to previous genotypic and antigenic studies and our phylogenetic analysis, in which the BJ-90 strain is closer to R. sibirica than R. mongolotimonae in the dendrogram inferred from comparison of the ompA encoding gene sequences, the BJ-90 strain should be considered a variant of R. sibirica.

Top

Jian Z. Zhang*†, Min Y. Fan†, Xue J. Yu‡, and D. Raoult*

Author affiliations: *Faculté de Médecine, Marseille, France; †Chinese Academy of Preventive Medicine, Beijing, P.R. China; ‡University of Texas Medical Branch, Galveston, Texas, USA

Top

References

  1. Fan  MY, Zhang  JZ, Chen  M, Yu  XJ. Spotted fever group rickettsioses in China. In: Rickettsiae and rickettsial diseases at the turn of the third millennium. Raoult D, Brouqui P, editors. Paris: Elsevier; 1999. p. 247-57.
  2. Yu  XJ, Fan  MY, Bi  DZ. Primary identification of spotted fever group rickettsiae isolated from Dermacentor sinicus in the Beijing area. Chin J Microbiol Immunol. 1991;11:305.
  3. Yu  XJ, Jin  Y, Fan  MY, Xu  GM, Liu  QH, Raoult  D. Genotypic and antigenic identification of two new strains of spotted fever group rickettsiae isolated from China. J Clin Microbiol. 1993;31:839.PubMed
  4. Xu  WB, Raoult  D. Taxonomic relationships among spotted fever group Rickettsiae as revealed by antigenic analysis with monoclonal antibodies. J Clin Microbiol. 1997;36:88796.
  5. Chen  M, Fan  MY, Bi  DZ, Zhang  JZ. Sequence analysis of PCR products amplified from five strains of spotted fever group rickettsiae with Rr with Rr 190. 70p and Rr 190. 602n primers. Acta Virol. 1998;42:913.PubMed
  6. Zhang  JZ, Fan  MY, Bi  DZ. Isolation and identification of spotted fever group rickettsiae BJ-93 strain. Chin J Microbiol Immunol. 1997;1:2833.
  7. Fournier  PE, Roux  V, Raoult  D. Phylogenetic analysis of spotted fever group rickettsiae by study of the outer surface protein OmpA. Int J Syst Bacteriol. 1998;48:83949. DOIPubMed
  8. Roux  V, Raoult  D. Phylogenetic analysis of the genus Rickettsia by 16S rDNA sequencing. Res Microbiol. 1995;146:38596. DOIPubMed
  9. Roux  V, Rydkina  E, Eremeeva  M, Raoult  D. Citrate synthase gene comparison, a new tool for phylogenetic analysis, and its application for the rickettsiae. Int J Syst Bacteriol. 1997;47:25261. DOIPubMed
  10. Stothard  DR, Fuerst  PA. Evolution analysis of the spotted fever and typhus group of Rickettsia using 16S rRNA gene sequences. Syst Appl Microbiol. 1995;18:5261.
  11. Weisburg  WG, Dobson  ME, Samuel  JE, Dasch  GA, Mallavia  LP, Baca  O, Phylogenetic diversity of the rickettsiae. J Bacteriol. 1989;171:42026.PubMed

Top

Cite This Article

DOI: 10.3201/eid0604.000426

Related Links

Top

Table of Contents – Volume 6, Number 4—August 2000

Page created: December 16, 2010
Page updated: December 16, 2010
Page reviewed: December 16, 2010
The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.
file_external