Cutler S J, Moss J, Fukunaga M, Wright D J, Fekade D, Warrell D
Department of Medical Microbiology, Charing Cross Hospital, London, United Kingdom.
Int J Syst Bacteriol. 1997 Oct;47(4):958-68. doi: 10.1099/00207713-47-4-958.
Borrelia recurrentis, the cause of louse-borne relapsing fever, has until recently been considered noncultivable, which has prevented characterization of this spirochete. We successfully cultivated 18 strains from patients with louse-borne relapsing fever and present the initial characterization of these isolates. Electron microscopy revealed spirochetal cells with pointed ends, an average wavelength of 1.8 microns, an amplitude of 0.8 micron, and 8 to 10 periplasmic flagella. The G+C ratio was 28.4 mol%. Whole DNA-DNA hybridizations showed similarity between the isolates of B. recurrentis but not with Borrelia hermsii, Borrelia parkeri, Borrelia turicatae, or the Lyme-associated borreliae. Sequencing studies of both the flagellin and 16S RNA genes revealed that the greatest similarity was between B. recurrentis and Borrelia duttonii. Analysis of the sodium dodecyl sulfate-polycarylamide gel electrophoresis profiles of strains revealed four groups based on the position of a major protein band (one of the groups showed some heterogeneity and was subdivided into four subgroups). Pulsed-field gel electrophoresis revealed five distinct patterns.
回归热疏螺旋体是虱传回归热的病原体，直到最近一直被认为无法培养，这阻碍了对这种螺旋体的特性描述。我们成功地从虱传回归热患者中培养出18株菌株，并展示了这些分离株的初步特性。电子显微镜显示螺旋体细胞两端尖锐，平均波长为1.8微米，振幅为0.8微米，有8至10根周质鞭毛。G+C比例为28.4摩尔%。全DNA-DNA杂交显示回归热疏螺旋体分离株之间具有相似性，但与赫氏疏螺旋体、帕克疏螺旋体、杜氏疏螺旋体或莱姆病相关疏螺旋体不具有相似性。鞭毛蛋白和16S RNA基因的测序研究表明，回归热疏螺旋体与达顿疏螺旋体之间的相似性最高。对菌株的十二烷基硫酸钠-聚丙烯酰胺凝胶电泳图谱分析显示，根据一条主要蛋白带的位置可分为四组（其中一组显示出一些异质性，并进一步细分为四个亚组）。脉冲场凝胶电泳显示出五种不同的模式。
