Fig. 5.
Cyclic di-GMP detection and relative quantification of cyclic di-GMP in recombinant P. aeruginosa strains. The LC–MS extracted ion chromatogram of cyclic di-GMP (m/z 691.102) in extracts of recombinant P. aeruginosa strains; (a) vector control (VC), (b) ml1419c and (c) ml1419cΔGGDEF. [13C]Adenosine was applied as an internal standard (retention time 7.702 min, m/z 269.1065). (d) The relative quantification demonstrated a significant increase in the abundance of cyclic di-GMP produced in P. aeruginosa expressing ml1419c as compared to VC and P. aeruginosa expressing ml1419cΔGGDEF, *P<0.0001. Experiments were performed with three biological and three technical replicates.