Isolation and identification of a novel spotted fever group rickettsia, strain IG-1, from Ixodes granulatus ticks collected on Orchid Island (Lanyu), Taiwan.
A novel species of spotted fever group (SFG) rickettsia, Rickettsia spp. IG-1, was identified and isolated from adult Ixodes granulatus ticks collected from Orchid Island (Lanyu), an islet located in southeastern Taiwan. Serum samples collected from the rodent host Rattus losea and SFG-positive human serum reacted with IG-1 using an immunofluorescence assay (IFA). Pairwise nucleotide sequence analysis of 16S rRNA (rrs), gltA, ompA, ompB, and sca4 shows that IG-1 belongs to SFG rickettsiae and had the highest nucleotide sequence similarities to Rickettsia slovaca and R. sibirica. Phylogenetic analysis of the ompA, ompB genes and sca4 shows that IG-1 is most closely related to R. honei. The results showed the sequence divergence of this novel isolate from those rickettsiae previously characterized using the criteria proposed by Fournier and others. Whether IG-1 is pathogenic for humans remains to be studied.
Tsai
Kun-Hsien
KH
Research and Diagnostic Center, Centers for Disease Control, Department of Health, Taipei, Taiwan, Republic of China.
Wang
Hsi-Chieh
HC
Chen
Chun-Hsien
CH
Huang
Jyh-Hsiung
JH
Lu
Hsiu-Ying
HY
Su
Chien-Ling
CL
Shu
Pei-Yun
PY
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D002460:Cell Line; D017753:Ecosystem; D005260:Female; D005843:Geography; D018884:Ixodes / Q000382:microbiology*; D051379:Mice; D008969:Molecular Sequence Data; D010802:Phylogeny; D051381:Rats; D012281:Rickettsia / Q000145:classification* / Q000302:isolation & purification*; D013624:Taiwan
D001426:Bacterial Proteins