Table 1.
Bacteria strains and plasmids used in this study.
Fig 1.
Motility and phenazine pigment production in P. aeruginosa wild-type PAO1 and fliA mutant.
(A) Swarming and swimming motility, (B) Pyocyanin production, and (C) Pyorubin production.
Fig 2.
Intracellular concentration of c-di-GMP in P. aeruginosa wild-type PAO1 and fliA mutant.
(A) Fluorescence intensity of cells on the periphery of swarming (Panels 1 and 2) and swimming (Panels 3 and 4) areas are presented. Panels 1 and 3, PAO1 [pCdrA–gfpC]; 2 and 4, ΔfliA [pCdrA–gfpC]. (B) Relative fluorescence units of PAO1 [pCdrA–gfpC] and ΔfliA [pCdrA–gfpC] under different growth conditions.
Table 2.
Expression levels of PDE/DGC-related genes based on the transcriptome analysis of ΔfliA compared with that of PAO1.
Fig 3.
Promoter activity of PDE-coding genes in P. aeruginosa wild-type PAO1 and fliA mutant strains.
(A) Promoters of PA4367 and PA5017 were predicted using the BPROM program. The DNA sequence of the predicted promoter regions, which were used in the GUS reporter assay, are shown in the block. The possible sigma factor binding sites are also indicated. (B) The promoter activity of PA4367 in wild-type PAO1 and ΔfliA is presented. All experiments were conducted in triplicate, and data are represented as mean ± standard error (n = 8; ***, p < 0.001).
Fig 4.
Effects of the c-di-GMP PDE-coding genes PA4367 and PA2133 on the swarming motility of the fliA mutant.
Bacterial culture of each strain were inoculated on the swarming and swimming plates and incubated at 37°C for 24 h. Images of the swarming (A) and swimming (B) pattern of the bacterial strains are presented.
Fig 5.
Effects of fliA and the c-di-GMP PDE-coding genes PA4367 and PA2133 on phenazine pigment production.
Pyocyanin (A) and pyorubin (B) produced by different P. aeruginosa strains were quantified after the cells were grown in a PB medium for 36 h. All experiments were conducted in triplicate, and data are represented as mean ± standard error (n = 3; **, p < 0.01).
Fig 6.
Effects of the c-di-GMP PDE coding genes PA4367 and PA2133 on flagellar synthesis in the P. aeruginosa fliA mutant.
Cells from overnight cultures grown in LB broth supplemented with 500 μg/ml carbenicillin and 0.5 mM IPTG were examined through TEM.