TY - JOUR
T1 - Rickettsia felis
T2 - Molecular characterization of a new member of the spotted fever group
AU - Bouyer, D. H.
AU - Stenos, J.
AU - Crocquet-Valdes, P.
AU - Moron, C. G.
AU - Popov, V. L.
AU - Zavala-Velazquez, J. E.
AU - Foil, L. D.
AU - Stothard, D. R.
AU - Azad, A. F.
AU - Walker, D. H.
PY - 2001
Y1 - 2001
N2 - In this report, placement of Rickettsia felis in the spotted fever group (SFG) rather than the typhus group (TG) of Rickettsia is proposed. The organism, which was first observed in cat fleas (Ctenocephalides felis) by electron microscopy, has not yet been reported to have been cultivated reproducibly, thereby limiting the standard rickettsial typing by serological means. To overcome this challenge, several genes were selected as targets to be utilized for the classification of R. felis. DNA from cat fleas naturally infected with R. felis was amplified by PCR utilizing primer sets specific for the 190 kDa surface antigen (rOmpA) and 17 kDa antigen genes. The entire 5513 bp rompA gene was sequenced, characterized and found to have several unique features when compared to the rompA genes of other Rickettsia. Phylogenetic analysis of the partial sequence of the 17 kDa antigen gene indicated that R. felis is less divergent from the SFG rickettsiae than from the TG rickettsiae. The data corroborate results from previous reports that analysed the citrate synthase, 16S rRNA, rompB (135 kDa surface antigen), metK, ftsY, poIA and dnaE genes that placed R. felis as a member of the SFG. The organism is passed transstadially and transovarially, and infection in the cat flea has been observed in the midgut, tracheal matrix, muscle, hypodermis, ovaries and testes.
AB - In this report, placement of Rickettsia felis in the spotted fever group (SFG) rather than the typhus group (TG) of Rickettsia is proposed. The organism, which was first observed in cat fleas (Ctenocephalides felis) by electron microscopy, has not yet been reported to have been cultivated reproducibly, thereby limiting the standard rickettsial typing by serological means. To overcome this challenge, several genes were selected as targets to be utilized for the classification of R. felis. DNA from cat fleas naturally infected with R. felis was amplified by PCR utilizing primer sets specific for the 190 kDa surface antigen (rOmpA) and 17 kDa antigen genes. The entire 5513 bp rompA gene was sequenced, characterized and found to have several unique features when compared to the rompA genes of other Rickettsia. Phylogenetic analysis of the partial sequence of the 17 kDa antigen gene indicated that R. felis is less divergent from the SFG rickettsiae than from the TG rickettsiae. The data corroborate results from previous reports that analysed the citrate synthase, 16S rRNA, rompB (135 kDa surface antigen), metK, ftsY, poIA and dnaE genes that placed R. felis as a member of the SFG. The organism is passed transstadially and transovarially, and infection in the cat flea has been observed in the midgut, tracheal matrix, muscle, hypodermis, ovaries and testes.
KW - 17 kDa gene
KW - Ctenocephalides felis
KW - Rickettsia felis
KW - Rickettsial outer-membrane protein A
KW - Tandem repeat domain
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U2 - 10.1099/00207713-51-2-339
DO - 10.1099/00207713-51-2-339
M3 - Article
C2 - 11321078
AN - SCOPUS:0035068816
SN - 1466-5026
VL - 51
SP - 339
EP - 347
JO - International Journal of Systematic and Evolutionary Microbiology
JF - International Journal of Systematic and Evolutionary Microbiology
IS - 2
ER -