Premium
Phylogenetic Analysis of Spotted Fever Group Rickettsiae Based on gltA, 17‐kDa, and rOmpA Genes Amplified by Nested PCR from Ticks in Japan
Author(s) -
Ishikura Mitsuhiro,
Ando Shuji,
Shinagawa Yasuhiro,
Matsuura Kumiko,
Hasegawa Sumiyo,
Nakayama Takashi,
Fujita Hiromi,
Watanabe Mamoru
Publication year - 2003
Publication title -
microbiology and immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.664
H-Index - 70
eISSN - 1348-0421
pISSN - 0385-5600
DOI - 10.1111/j.1348-0421.2003.tb03448.x
Subject(s) - biology , genotype , tick , felis , haemaphysalis longicornis , ixodes persulcatus , phylogenetic tree , gene , ixodidae , nested polymerase chain reaction , genetics , virology , polymerase chain reaction , cats , computer science , embedded system
In order to understand the natural situation of rickettsiae in the ticks in Japan, the rickettsial genes, gltA gene, rOmpA gene, and 17‐kDa gene, were amplified from the ticks by nested PCR. The prevalences of rickettsial gltA genes among Haemaphysalis formosensis, H. longicornis, H. megaspinosa, Ixodes ovatus, H. flava, H. kitaokai , and I. persulcatus were 62, 57, 24, 24, 19, 13, and 10%, respectively; 26% (186/722) being the average. The gltA genes amplified from the ticks were classified into 9 genotypes (I to IX) by the difference in nucleotide sequences. Genotype I was detected from 7 species of ticks. Genotype II mainly was detected from H. longicornis and H. formosensis . Genotypes III and VII mainly were detected from H. flava and I. ovatus . The polarization in the distribution of genotypes among regions where the ticks were collected was not clear. Based on the phylogenetic analysis of the three genes presented here, genotypes I, III, and IV (detected from H. formosensis, H. hystricia , and I. ovatus ) are genetically close with each other, but rickettsiae of the same property still have not been isolated from ticks anywhere in the world. These genotypes should be considered as new species among SFG rickettsiae. Genotype II was identical with strain FUJ‐98, genetically close to R. japonica which has been isolated from ticks in China. Genotype V was identical with R. felis and strain California 2 isolated from the cat flea. This is the first report on the detection of R. felis from ticks. Genotype VI detected from Ixodes sp. did not seem to belong to genus Rickettsia . Based on the previous antigenic data and the phylogenetic analysis presented here, Genotype VII should be considered a variant of R. helvetica and genotype VIII detected from I. ovatus and I. persulcatus were identical with R. helvetica . Genotype IX detected from I. nipponensis was genetically close to the strains IRS3, IRS4, and IrR/Munich isolated from I. ricinus in Slovakia and German.