Ozawa Y, Mizushima S, Mizuno T
Laboratory of Microbiology, School of Agriculture, Nagoya University, Japan.
FEMS Microbiol Lett. 1990 Mar 15;56(3):295-9. doi: 10.1016/s0378-1097(05)80057-6.
A novel type of osmoregulatory mutant of Escherichia coli K-12 exhibiting constitutive expression of the ompC gene was isolated and characterized at the molecular level. In this particular mutant (cec; constitutive expression of OmpC), an insertion sequence (IS-1) was found to be located at right upstream of the regulatory sequence for the ompC promoter. We demonstrate that the IS1 insertion observed in the cec mutant does not provide the ompC gene with an artificial promoter, but rather perturbs normal regulation of the ompC promoter, which is mediated by the regulatory gene, ompR.
分离出了一种新型的大肠杆菌K-12渗透调节突变体，该突变体表现出ompC基因的组成型表达，并在分子水平上进行了表征。在这个特定的突变体（cec；OmpC的组成型表达）中，发现一个插入序列（IS-1）位于ompC启动子调控序列的右上游。我们证明，在cec突变体中观察到的IS1插入并没有为ompC基因提供一个人工启动子，而是扰乱了由调控基因ompR介导的ompC启动子的正常调控。
