Knott V, Blake D J, Brownlee G G
Sir William Dunn School of Pathology, University of Oxford, UK.
Nucleic Acids Res. 1989 Aug 11;17(15):5901-12. doi: 10.1093/nar/17.15.5901.
Ordered sets of cosmids derived from E. coli K-12 803 overlap the 6 remaining gaps left in the physical map of strain W3110. We present detailed restriction maps of the gaps and surrounding regions, thus providing a comparison of about 30% of the genome of the two E. coli strains. Our analysis shows that there is a high degree of homology between the strains, with only occasional restriction fragment differences. However, the large inversion occurring between rrnD (72.1') and rrnE (90.4') in strain W3110 is absent in strain 803. Instead, a new inversion and adjacent deletion near argF is present in strain 803. The distribution of cosmid clones at, and adjacent to, the gaps shows that all gaps except one were difficult to clone in both lambda and cosmid clones. A low copy number cosmid vector, pOU61cos, developed previously, was essential for cloning 3 of the 8 gaps.
来自大肠杆菌K-12 803的有序黏粒文库覆盖了W3110菌株物理图谱中剩余的6个缺口。我们展示了这些缺口及周边区域的详细限制性图谱，从而对两种大肠杆菌菌株约30%的基因组进行了比较。我们的分析表明，这两种菌株之间存在高度同源性，仅偶尔存在限制性片段差异。然而，W3110菌株中rrnD（72.1'）和rrnE（90.4'）之间发生的大片段倒位在803菌株中不存在。相反，803菌株中存在一个新的倒位以及argF附近的相邻缺失。黏粒克隆在缺口处及相邻区域的分布表明，除了一个缺口外，其他所有缺口在λ噬菌体和黏粒克隆中都难以克隆。先前开发的低拷贝数黏粒载体pOU61cos对于克隆8个缺口中的3个至关重要。
