Bonamy C, Hirschbein L, Szulmajster J
J Bacteriol. 1973 Mar;113(3):1296-306. doi: 10.1128/jb.113.3.1296-1306.1973.
The incorporation of radioactive uracil into 50s and 30s ribosomal subunits and ribosomal ribonucleic acid (rRNA) was studied during the growth cycle of different sporogenic and asporogenic strains of Bacillus subtilis. It was found that partially synchronized cultures of the strains examined incorporated labeled uracil into the two ribosomal subunit species and rRNA during sporulation and during the stationary phase of the asporogenic strains. Kinetic studies have shown that, compared to vegetative cells, the percentage of uracil incorporated into the ribosomal subunits of cells taken 30 min after the end of exponential growth was decreased by about 25 to 35%. This decrease, however, appeared to be a general characteristic of stationary-phase cells and seems to depend on the nature of the sporulation medium and to some extent on the nature of the strain but not on the sp(+) or sp(-) phenotype of the strain. Moreover, by use of actinomycin D it was shown that the labeled uracil incorporated, in the presence of the drug, during the sporulation period was located in the ribosomal subunits (stable RNA). Based on these results, we concluded that during sporulation ribosomal genes are transcribed and consequently rRNA continues to be synthesized, although to a lesser extent than during vegetative growth. These results are discussed in the light of those obtained by Hussey et al.
在枯草芽孢杆菌不同产孢和不产孢菌株的生长周期中，研究了放射性尿嘧啶掺入50S和30S核糖体亚基以及核糖体核糖核酸（rRNA）的情况。结果发现，在所检测菌株的部分同步培养物中，在产孢期间以及不产孢菌株的稳定期，标记的尿嘧啶会掺入这两种核糖体亚基类型和rRNA中。动力学研究表明，与营养细胞相比，指数生长期结束30分钟后采集的细胞中，掺入核糖体亚基的尿嘧啶百分比降低了约25%至35%。然而，这种降低似乎是稳定期细胞的普遍特征，似乎取决于产孢培养基的性质，在一定程度上还取决于菌株的性质，但不取决于菌株的sp(+)或sp(-)表型。此外，通过使用放线菌素D表明，在产孢期间药物存在的情况下掺入的标记尿嘧啶位于核糖体亚基（稳定RNA）中。基于这些结果，我们得出结论，在产孢期间核糖体基因被转录，因此rRNA继续合成，尽管合成程度低于营养生长期间。将根据Hussey等人获得的结果对这些结果进行讨论。
