FIG. 4.

σ^E-independent strengths of the long and short promoters. The graph compares long and short promoter strengths in σ^E overexpressing (o/exp; derivatives of CAG58200 carrying the rpoE overexpression plasmid pLC245) and no-σ^E (delta sE; derivatives of CAG22216) strains. Only nine promoters gave significant σ^E-independent activities. All promoter strengths were determined from exponential-phase cultures (OD₆₀₀ of 0.7 to 1.4) grown at 32°C in LB. σ^E overexpression was induced by growth in 100 μm IPTG. The bars represent the averages of three independent experiments, and error bars represent 1 standard deviation.