Zaniewski R, Petkaitis E, Deutscher M P
J Biol Chem. 1984 Oct 10;259(19):11651-3.
A multiple mutant strain of Escherichia coli containing mutations affecting the exoribonucleases, RNase II, RNase D, and RNase BN, and also the endonuclease, RNase I, was constructed by P1-mediated transduction. Extracts of the mutant strain were lacking the aforementioned RNase activities. The multiple mutant displayed normal growth in both rich and minimal media at a variety of temperatures, recovered from starvation essentially as the wild-type parent, and could support the growth of a variety of bacteriophages. In addition, RNA synthesis was normal and no precursor RNA accumulation was observed. The properties of the mutant strain indicate that the three exoribonucleases are not essential for the viability of E. coli. The implications of these findings to our understanding of RNA processing and degradation are discussed.
通过P1介导的转导构建了一种大肠杆菌多突变株，该菌株含有影响外切核糖核酸酶RNase II、RNase D和RNase BN以及内切核酸酶RNase I的突变。突变株的提取物缺乏上述核糖核酸酶活性。该多突变株在多种温度下的丰富培养基和基本培养基中均能正常生长，从饥饿状态恢复的情况与野生型亲本基本相同，并且能够支持多种噬菌体的生长。此外，RNA合成正常，未观察到前体RNA积累。突变株的特性表明这三种外切核糖核酸酶对于大肠杆菌的生存力并非必不可少。讨论了这些发现对我们理解RNA加工和降解的意义。
