Figure 5.
Effect of L20 overproduction on the transcription profile of the infC operon. Northern analysis of total RNA of a B. subtilis wild-type strain harboring plasmid pHML17 carrying an IPTG inducible copy of the rplT (L20) gene was performed using two different probes. (A) RNA was separated on a 0.8% agarose gel and probed with an infC specific probe including the entire leader sequence (see Materials and methodssection). (B) RNA separated on a 8% polyacrylamide gel was probed with oligonucleotide HP1080 complementary to positions +8 to +34 of the infC leader. Where indicated IPTG (1 mM) was added to mid-log cultures for 20 min prior to isolation of the RNA. RT = read-through transcript, T = terminated transcript. The positions of the molecular size markers are indicated. Percentages of read-through transcripts are indicated below the gel.