RESUMO
Eleven pure cultures of Borrelia from 3 species of wild rodents (Apodemus agrarius, Mus formosanus, Rattus losea) captured in Taichung, located in the center of Taiwan island, and on Kinmen Island were characterized. Five isolates showed restriction fragment length polymorphism (RFLP) patterns of 5S-23S rRNA gene intergenic spacer sequences identical to those of strains 5MT and 10MT, identified as Borrelia valaisiana, which were isolated in the southern tip of South Korea. Although the remaining six isolates showed novel RFLP patterns, these isolates showed more similarity to members of B. valaisiana from Korea, Japan and Europe based on 16S rRNA gene and flagellin gene sequences. This led us to speculate that transmission and proliferation of this type of borrelia occurred between Taiwan and the southern part of South Korea.
Assuntos
Infecções por Borrelia/veterinária , Borrelia/genética , Doenças dos Roedores/microbiologia , Animais , Anticorpos Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Sequência de Bases , Borrelia/classificação , Borrelia/imunologia , Borrelia/isolamento & purificação , Infecções por Borrelia/microbiologia , Flagelina/genética , Genes Bacterianos , Geografia , Humanos , Dados de Sequência Molecular , Muridae , Filogenia , Polimorfismo de Fragmento de Restrição , RNA Bacteriano , RNA Ribossômico 16S , Ratos , Roedores , Análise de Sequência de RNA , TaiwanRESUMO
A survey was performed for Lyme disease borrelia in the southern part of China, in Zhejiang, Sichuan and Anhui provinces, along the Yangtze River valley, in May of 1997 and 1998. Twenty isolates from Ixodes granulatus, Ixodes ovatus, Apodemus agrarius and Niviventer confucianus were obtained. These isolates were characterized by RFLP of the 5S-23S rDNA intergenic spacer, sequence analysis of the intergenic spacer, 16S rDNA and flagellin gene, DNA-DNA hybridization analysis, SDS-PAGE and Western blotting with mAbs. Six isolates from A. agrarius, five from I. granulatus collected in Zhejiang province and one from N. confucianus in Sichuan province were highly similar to strains 10MT and 5MT isolated in Korea and classified as Borrelia valaisiana. Four isolates from A. agrarius and I. granulatus collected in Zhejiang province generated unique RFLP patterns and phylogenetic analysis of the 16S rDNA and flagellin gene sequences suggested that the isolates should be classified as B. valaisiana. Furthermore, three isolates (CMN1a, CNM2, CMN3T) from N. confucianus captured in Sichuan province and one (CWO1) from I. ovatus in Anhui province showed lower 165 rDNA sequence similarity (less than 99.0%) to sequences of previously described Lyme disease-related Borrelia species. DNA-DNA hybridization results revealed that strains CMN3T and CMN1a were clearly distinct from all other known Lyme disease Borrelia species. Electron microscope observation showed the spirochaetes to be morphologically similar to those of Borrelia, but the cells contained only four periplasmic flagella inserted at each end of the spirochaetes. Based on these results, a new Borrelia species, Borrelia sinica sp. nov., is proposed. Strain CMN3T is the type strain of this new species.
Assuntos
Antígenos de Bactérias , Borrelia/classificação , Ixodes/microbiologia , Lipoproteínas , Doença de Lyme/veterinária , Muridae/microbiologia , Doenças dos Roedores/microbiologia , Animais , Anticorpos Monoclonais/imunologia , Antígenos de Superfície/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas , Composição de Bases , Borrelia/genética , Borrelia/isolamento & purificação , China/epidemiologia , DNA Espaçador Ribossômico/análise , Flagelina/genética , Doença de Lyme/epidemiologia , Doença de Lyme/microbiologia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , RNA Ribossômico 5S/genética , Doenças dos Roedores/epidemiologia , Análise de Sequência de DNARESUMO
In May 1999, field surveys of Lyme disease spirochetes were conducted around the Tianshan Mountains in Xinjiang Uygur Autonomous Region in northwestern People's Republic of China. Ixodes persulcatus ticks were obtained in a Tianchi Lake valley with primary forest, while the tick fauna was poor in the semidesert or at higher altitudes in this region. Species identities were confirmed by molecular analysis in which an internal transcribed spacer sequence was used. Of 55 adult ticks, 22 (40%) were positive for spirochetes as determined by Barbour-Stoenner-Kelly culture passages. In addition, some rodents, including Apodemus uralensis (5 of 14 animals) and Cricetulus longicaudatus (the only animal examined), and some immature stages of I. persulcatus (4 of 11 ticks) that had fed on A. uralensis were positive for spirochetes. Based on 5S-23S rRNA intergenic spacer restriction fragment length polymorphism analysis and reactivity with monoclonal antibodies, 35 cultures (including double isolation cultures) were identified as Borrelia garinii (20 isolates, including 9 Eurasian pattern B isolates and 11 Asian pattern C isolates), Borrelia afzelii (10 pattern D isolates), and mixed cultures (5 cultures, including isolates that produced B. garinii patterns B and C plus B. afzelii pattern D). These findings revealed that Lyme disease pathogens are distributed in the mountainous areas in northwestern China even though it is an arid region, and they also confirmed the specific relationship between I. persulcatus and genetic patterns of Borrelia spp. on the Asian continent.