Ganesan A K, Seawell P C
Mol Gen Genet. 1975 Dec 1;141(3):189-205. doi: 10.1007/BF00341799.
We have examined lexA1 uvrA6 and recF143 uvrBdelta derivatives of Escherichia coli K-12 for post-replication repair and DNA synthesis after UV irradiation. Compared to corresponding lex+ rec+ strains, we found that the lexA and recF cells were defective in (1) converting short DNA segments synthesized after irradiation to DNA of normal size; (2) synthesizing high molecular weight DNA after irradiation; (3) transferring pyrimidine dimers from irradiated DNA into unirradiated daughter strands. Our results support the hypothesis that after UV irradiation the formation of large DNA molecules in excision-deficient cells of E.coli depends directly or indirectly upon joining short DNA segments into longer strands, concomitant with the transfer of DNA from irradiated tamplates into unirradiated daughter strands. This process appears to require the activity of lexA and recF genes.
我们检测了大肠杆菌K-12的lexA1 uvrA6和recF143 uvrBδ衍生物在紫外线照射后的复制后修复和DNA合成情况。与相应的lex⁺ rec⁺菌株相比，我们发现lexA和recF细胞在以下方面存在缺陷：（1）将照射后合成的短DNA片段转化为正常大小的DNA；（2）照射后合成高分子量DNA；（3）将嘧啶二聚体从照射过的DNA转移到未照射的子代链中。我们的结果支持这样的假设，即紫外线照射后，大肠杆菌切除缺陷细胞中大分子DNA的形成直接或间接地依赖于将短DNA片段连接成长链，同时将DNA从照射过的模板转移到未照射的子代链中。这个过程似乎需要lexA和recF基因的活性。
