FIG. 6.

Quality check of RNA used for DNA macroarray analysis. A total of 5 μg of RNA isolated from exponentially growing cells before and 10 min after addition of norvaline from the wild type (A) and the relA mutant (B), respectively, was separated through a 1.2% agarose gel and stained with ethidium bromide (middle); the bands for 16S and 23S RNA are indicated. These ethidium bromide-stained gels were used for Northern blot analysis. To check the transcription of yvyD and tufA, the blotted membrane was divided as indicated in the figure. As suggested from previous studies and from protein data, transcriptional induction of yvyD, as well as transcriptional repression of tufA, occurred only in B. subtilis wild-type BR16. The positions of the RNA molecular size standard bands and the sizes of the yvyD or tufA transcripts are indicated. (C) Transcriptional organization of the str operon (which contains tufA).