Meta-analyses of P. aeruginosa transcriptomes suggest that DgcH is an invariable DGC. (A) Relative expression profiling patterns of dgcH in P. aeruginosa meta-array analyses. In total, 162 conditions were tested for expression analyses of dgcH, and we found that there was no significant difference within these conditions except one. The x axis represents 162 different conditions, and the y axis indicates the expression values calculated from a meta-analysis of the GEO data sets. The expression value is on a log2 scale. (B) mucR and dgcH expression in different temperatures. Temperatures of 28 and 37°C were used to detect the expression of mucR and dgcH promoter fusion, with GFP as the readout. (C) dgcH expression under different environmental conditions. Freshly inoculated P. aeruginosa cells were treated with a final concentration of 10 mM H2O2 and 300 μg/ml carbenicillin, grown at 28°C, and incubated with different nutritional media, namely, Jensen’s medium, MH medium (BD), and PIA medium (BD). (D) dgcH expression in different genetic backgrounds. The GFP reporter strain pProbe-dgcH was conjugated into multiple mutant strains of P. aeruginosa and tested for promoter activity of dgcH in these strains. (B to D) Arbitrary fluorescence units were defined by the GFP intensity calibrated using the OD600.