Frasch A C, Hajduk S L, Hoeijmakers J H, Borst P, Brunel E, Davison J
Biochim Biophys Acta. 1980 May 30;607(3):397-410. doi: 10.1016/0005-2787(80)90150-1.
We have analyzed the kinetoplast DNA for Trypanosoma equiperdum (American Type Culture Collection 30019) and two dyskinetoplastic strains derived from it. The DNA networks from the kinetoplastic strain are made up of catenated mini-circles and maxi-circles, like the networks from the closely-related Trypanosoma brucei. The mini-circles of T. equiperdum lack the pronounced sequence heterogeneity of T. brucei mini-circles, as shown by the fragment distribution of restriction digests and by the predominance of well-matched duplexes in electron micrographs of renatured DNA. The electrophoretic analysis of kinetoplast DNA digested with various restriction endonucleases shows the maxi-circle of T. equiperdum to consist of circular DNA molecules of 8.4 x 10(6) daltons, without size or sequence heterogeneity or repetitious segments. A comparison of the sequence by restriction endonuclease fragmentation and hybridization shows extensive sequence homology. The size difference between both maxi-circles is due to the deletion of one continuous segment of 5.10(6) daltons. In the two dyskinetoplastic strains, we cannot detect DNA sequences that hybridize with kinetoplast DNA from T. brucei or from the kinetoplastic strain of T. equiperdum. In one of these strains, a 'low-density' DNA fraction contained a simple sequence DNA, cleaved by restriction endonuclease HindIII into fragments of 180 base-pairs and multimers of this. The relation of this DNA to kinetoplast DNA, if any, is unknown.
我们分析了马媾疫锥虫（美国模式培养物保藏库30019）及其衍生的两个运动不能性动基体菌株的动基体DNA。动基体菌株的DNA网络由连环的微小环和大环组成，类似于密切相关的布氏锥虫的网络。马媾疫锥虫的微小环比布氏锥虫的微小环缺乏明显的序列异质性，这通过限制性酶切片段分布以及复性DNA电子显微照片中匹配良好的双链体占优势得以显示。用各种限制性内切酶消化动基体DNA的电泳分析表明，马媾疫锥虫的大环由8.4×10⁶道尔顿的环状DNA分子组成，没有大小或序列异质性或重复片段。通过限制性内切酶片段化和杂交对序列进行比较显示出广泛的序列同源性。两个大环之间的大小差异是由于一个5×10⁶道尔顿的连续片段缺失所致。在这两个运动不能性动基体菌株中，我们无法检测到与布氏锥虫或马媾疫锥虫动基体菌株的动基体DNA杂交的DNA序列。在其中一个菌株中，一个“低密度”DNA组分含有简单序列DNA，被限制性内切酶HindIII切割成180个碱基对的片段及其多聚体。该DNA与动基体DNA的关系（如果有的话）尚不清楚。
