
Simultaneous Detection of Anaplasma marginale and a New Ehrlichia Species Closely Related to Ehrlichia chaffeensis by Sequence Analyses of 16S Ribosomal DNA in Boophilus microplus Ticks from Tibet
Author(s) -
Bin Wen,
Rui Jian,
Zhang YouZhi,
Rong Chen
Publication year - 2002
Publication title -
journal of clinical microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.349
H-Index - 255
eISSN - 1070-633X
pISSN - 0095-1137
DOI - 10.1128/jcm.40.9.3286-3290.2002
Subject(s) - ehrlichia chaffeensis , ehrlichia , biology , anaplasma , 16s ribosomal rna , nested polymerase chain reaction , ribosomal rna , virology , anaplasmataceae , 23s ribosomal rna , sequence analysis , ehrlichiosis , microbiology and biotechnology , gene , polymerase chain reaction , genetics , tick , ribosome , rna
To identify ehrlichial agents in Boophilus microplus ticks, DNA samples of B. microplus collected from the Tibet Autonomous Region and Sichuan Province of China were screened by a nested PCR. Sixteen of 43 (37%) DNA samples of B. microplus from Tibet were positive in nested PCR analysis. All 27 samples from Sichuan were negative. The screen identified two ehrlichial agents based on different 16S rRNA genes that were found after amplifying and sequencing the 5'-end fragments of the 16S rRNA genes. One sequence was identical to that of the gene of Anaplasma marginale, an etiological agent of animal anaplasmosis. The other sequence was most similar to that of the gene of Ehrlichia chaffeensis, an etiological agent of human monocytic ehrlichiosis. The sequence of 1,501 bases from the novel ehrlichial agent was obtained and showed the greatest levels of sequence similarity (97 to 98%) to 16S rRNA gene sequences of the members of the E. canis group of the genus EHRLICHIA: Sequence comparison of the 16S rRNA gene with the members of the genus Ehrlichia reveals that the novel ehrlichial agent detected in B. microplus ticks is a new species of the genus Ehrlichia and is most closely related to E. chaffeensis.