Plasmids containing Pfim3-15C, Pfim3-15C lacking DRE (H13), PgapA*, or PgapA* containing DRE (PgapA-DRE) were introduced in single copy in the chromosome of B. pertussis strain BP536 and B. bronchiseptica strain RB50, or as plasmid multi-copies in E. coli strain SM10. The resulting strains were grown at 37°C on BG plates for Bordetella strains, or on LB plates for the E. coli strain, and analyzed for the light output as described in Experiment Procedures. The activity of the DRE-containing promoter (solid box, Pfim3-15C, PgapA-DRE) is expressed as a percentage of that of the DRE-free promoter (open box, H13, PgapA) in each species. Error bars indicate standard deviation as calculated from the results of four independent assays.