Kopecky A L, Copeland D P, Lusk J E
Proc Natl Acad Sci U S A. 1975 Nov;72(11):4631-4. doi: 10.1073/pnas.72.11.4631.
Conditions permitting survival (colony formation) of E. coli after treatment with colicin K have been found. Survival required K+ and Mg2+ at concentrations high enough to replace the intracellular ions lost from colicintreated cells. Either glucose minimal medium or broth could support survival. Survival was still observed after colicin-promoted efflux of Rb+ and decline in ATP levels had occurred, and after the period during which treatment with trypsin could rescue the cells on media containing low concentrations of K+. In an adenosinetriphosphate (ATP phohsphohydrolase, EC 3.6.1.3) deficient (uncA) mutant, survival after colicin treatment was observed at lower Mg2+ concentrations than those required by the wild type, and Rb+ could replace K+. Cells treated with colicin E1 (but not with colicin I2, E3, or Ib) also survived under conditions permitting survival of colicin K.
已发现用大肠菌素K处理后大肠杆菌能够存活(形成菌落)的条件。存活需要足够高浓度的K⁺和Mg²⁺来替代经大肠菌素处理的细胞中丢失的细胞内离子。葡萄糖基本培养基或肉汤均可支持存活。在大肠菌素促使Rb⁺外流且ATP水平下降后,以及在用胰蛋白酶处理可使细胞在含低浓度K⁺的培养基上存活的时间段之后,仍观察到了存活现象。在缺乏三磷酸腺苷(ATP磷酸水解酶,EC 3.6.1.3)的(uncA)突变体中,大肠菌素处理后的存活在比野生型所需浓度更低的Mg²⁺浓度下即可观察到,且Rb⁺可替代K⁺。用大肠菌素E1(但不用大肠菌素I2、E3或Ib)处理的细胞在允许大肠菌素K存活的条件下也能存活。