srf - 2020和srf - 801的克隆与初步特性分析，这两个recF部分抑制突变位于大肠杆菌K - 12的recA基因座中。

Cloning and preliminary characterization of srf-2020 and srf-801, the recF partial suppressor mutations which map in recA of Escherichia coli K-12.

作者信息

Wang T C, Madiraju M V, Templin A, Clark A J

机构信息

Department of Molecular Biology, Chang Gung Medical College, Kwei-San, Tao-Yuan, Taiwan.

出版信息

Biochimie. 1991 Feb-Mar;73(2-3):335-40. doi: 10.1016/0300-9084(91)90221-l.

DOI:10.1016/0300-9084(91)90221-l

Abstract

We have located the single nucleotide changes suffered in recA sequence of 2 recF partial suppressor mutations: srf-2020 at codon 121 and srf-801 at codon 257. srf-2020 changes codon 121 from threonine (ACC) to isoleucine (ATC). srf-801 changes codon 257 from glutamine (CAG) to proline (CCG). Consequently these mutations were renamed recA2020 and recA801 respectively. Preliminary characterization of recA2020 revealed that it is transdominant to recA+, like recA803, another recF partial suppressor. Interactions of recA2020 with recA803 were examined using genetic studies. Heterozygotes containing recA2020 and recA803 failed to produce a synergistic suppression effect in suppressing the recF deficiency. Presence of both recA2020 and recA803 mutations in the same recA gene also failed to produce any greater amount of UV resistance to a uvrA6recF143del(recA) strain indicating no interactions between these suppressors.

摘要

我们已经定位了2个recF部分抑制突变体的recA序列中发生的单核苷酸变化：位于密码子121的srf - 2020和位于密码子257的srf - 801。srf - 2020将密码子121由苏氨酸（ACC）变为异亮氨酸（ATC）。srf - 801将密码子257由谷氨酰胺（CAG）变为脯氨酸（CCG）。因此，这些突变分别重新命名为recA2020和recA801。recA2020的初步特征表明，与另一个recF部分抑制突变体recA803一样，它对recA +呈反式显性。使用遗传学研究检测了recA2020与recA803之间的相互作用。含有recA2020和recA803的杂合子在抑制recF缺陷方面未能产生协同抑制作用。在同一个recA基因中同时存在recA2020和recA803突变，也未能对uvrA6recF143del(recA)菌株产生更强的紫外线抗性，这表明这些抑制突变体之间没有相互作用。