This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Bonamy, C. Articles by Szulmajster, J. Search for Related Content PubMed PubMed Citation Articles by Bonamy, C. Articles by Szulmajster, J.

 Previous Article  |  Next Article 

J Bacteriol. 1973 March; 113(3): 1296-1306
Copyright © 1973 American Society for Microbiology. All Rights Reserved.

Synthesis of Ribosomal Ribonucleic Acid During Sporulation of Bacillus subtilis

¹ Laboratoire d'Enzymologie du Centre National de la Recherche Scientifique, 91-Gif-sur-Yvette, France, and Institut de Microbiologie, Université Paris-Sud, 91-Orsay, France

ABSTRACT

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.