Louarn J M, Louarn J, François V, Patte J
Centre de Biochimie et de Génétique Cellulaires, Centre National de la Recherche Scientifique, Toulouse, France.
J Bacteriol. 1991 Aug;173(16):5097-104. doi: 10.1128/jb.173.16.5097-5104.1991.
The frequency of excisive homologous recombination has been measured at various positions along the Escherichia coli chromosome. The reporter system makes use of a lambda cI857 prophage integrated by homologous recombination within Tn5 or Tn10 transposons already installed at known positions in the E. coli chromosome. The excision frequency per cell and per generation was determined by monitoring the evolution of the relative number of temperature-resistant (cured) bacteria is a function of the age of the cultures. Excisions, due to RecA-dependent homologous exchanges, appeared to occur more frequently in the preferential termination zone for chromosome replication. The highest frequency of excision observed is compatible with a recombination event at each replication cycle in this region. On the basis of these data, we propose a model involving homologous recombination in the final steps of bacterial chromosome replication and separation.
已在大肠杆菌染色体的不同位置测量了切除性同源重组的频率。该报告系统利用通过同源重组整合到已安装在大肠杆菌染色体已知位置的Tn5或Tn10转座子内的λcI857原噬菌体。通过监测耐温（治愈）细菌相对数量的演变作为培养物年龄的函数，确定每个细胞和每一代的切除频率。由于RecA依赖性同源交换导致的切除似乎在染色体复制的优先终止区更频繁地发生。观察到的最高切除频率与该区域每个复制周期的重组事件一致。基于这些数据，我们提出了一个在细菌染色体复制和分离的最后步骤中涉及同源重组的模型。
