FIG. 1.
(A) Kanamycin resistance arising from the basal activity of the sigE promoter in the ΔcseA null mutant (J2142) carrying the sigEp-neo reporter plasmid pIJ6880. Approximately 105 spores (in 10 μl of 20% glycerol) were spotted onto MMCGT plates containing different amounts of kanamycin. Plates were incubated at 30°C for 4 days. The results shown for the wild type (M600) and for the cseB and sigE null mutants have been reported previously (14). (B) S1 nuclease protection analysis of the sigE transcript in S. coelicolor M600 and the ΔcseA null mutant (J2172) following induction with vancomycin. RNA was isolated at 30-min intervals up to 90 min from S. coelicolor M600 and J2172 grown in NMMP liquid medium containing 2 mM MgCl2 after induction with 10 μg/ml vancomycin. Relative signal strengths were quantified on a phosphorimager; each signal is expressed as a percentage of the strongest signal.