Fig 6. Role of CTD motifs for sensing of Rel_Sau in vivo.

(p)ppGpp⁰ mutant was complemented with different rel constructs expressed from the native promoter (A). The black crosses (A) represent mutations as indicated in Fig 1A. Strains were grown in rich medium to OD₆₀₀ = 0.3 and then split in cultures with and without 0.3 μg/ml mupirocin. For Northern analysis (B) RNA was isolated from cells 30 minutes after reaching OD₆₀₀ = 0.3 and hybridized with digoxigenin-labeled probes. The 16S rRNA detected in the ethidium bromide-stained gels is indicated as loading control in the bottom lane. Growth was monitored after reaching OD₆₀₀ = 0.3 after which 0.3. μg/ml mupirocin was added (C).