Milkman R, Bridges M M
Department of Biology, University of Iowa, Iowa City 52242.
Genetics. 1990 Nov;126(3):505-17. doi: 10.1093/genetics/126.3.505.
PCR fragments, 1500-bp, from 15 previously sequenced regions in the Escherichia coli chromosome have been compared by restriction analysis in a large set of wild (ECOR) strains. Prior published observations of segmental clonality are confirmed: each of several sequence types is shared by a number of strains. The rate of recombinational replacement and the average size of the replacements are estimated in a set of closely related strains in which a clonal frame is dotted with occasional stretches of DNA belonging to other clones. A clonal hierarchy is described. Some new comparative sequencing data are presented.
通过对大量野生型(ECOR)大肠杆菌菌株进行限制性分析,比较了来自大肠杆菌染色体上15个先前已测序区域的1500碱基对PCR片段。先前发表的关于片段克隆性的观察结果得到了证实:几种序列类型中的每一种都被许多菌株共享。在一组密切相关的菌株中估计了重组替换率和替换的平均大小,在这些菌株中,克隆框架点缀着偶尔属于其他克隆的DNA片段。描述了一个克隆层次结构。还展示了一些新的比较测序数据。