Normalized fold change of promoter activity in Δcrp in relative to WT
Plasmid copy number
β-Galactosidase activity (miller units) was detected as the promoter activity. An extremely low promoter activity was detected for the Δcrp or WT transformed with empty pRS551 (data not shown). Copy number of recombinant pRS551 (PsycO-lacZ) was determined by real-time quantitative PCR, the detecting fold change of plasmid copy number was set to be 1 to generate a normalization factor that was subsequently used for generating the normalized fold change of promoter activity (miller units) in the Δcrp in relative to the WT. Each experiment was done in triplicate.