Brayton K A, Fehrsen J, de Villiers E P, van Kleef M, Allsopp B A
Onderstepoort Veterinary Institute, South Africa.
Vet Parasitol. 1997 Oct;72(2):185-99. doi: 10.1016/s0304-4017(97)00020-4.
The causative agent of heartwater, the rickettsia Cowdria ruminantium, is very poorly understood at the molecular level owing to a profound lack of suitable tools. We have developed an immunoaffinity chromatographic method to purify C. ruminantium from host cell components and the purified rickettsial cells have been used to prepare substantially pure Cowdria DNA. This DNA has been used to construct what we believe to be the first fully representative C. ruminantium expression library. A clone containing the complete Cowdria map1 gene has been isolated and sequenced. This gene has been expressed in E. coli cells from the native Cowdria promoter, suggesting that the mechanisms for gene transcription and translation are similar between these two organisms. Parts of three other Cowdria genes have also been isolated and sequenced.
由于严重缺乏合适的工具，心水病的病原体——反刍兽考德里氏体（Cowdria ruminantium）在分子水平上的情况仍知之甚少。我们开发了一种免疫亲和色谱方法，用于从宿主细胞成分中纯化反刍兽考德里氏体，纯化后的立克次氏体细胞已被用于制备基本纯净的考德里氏DNA。该DNA已被用于构建我们认为的首个具有完全代表性的反刍兽考德里氏体表达文库。一个包含完整考德里氏map1基因的克隆已被分离并测序。该基因已在大肠杆菌细胞中由天然考德里氏启动子进行表达，这表明这两种生物体之间的基因转录和翻译机制相似。另外三个考德里氏基因的部分片段也已被分离并测序。
