Fig 5.

Inactivation of dipA impairs swarming motility but enhances initial attachment and polysaccharide levels at the posttranscriptional level. (A) Swarming motility of P. aeruginosa PA14 strains inactivated or (over)expressing dipA following 48 h of growth on M8 agar. (B) Swarming motility of P. aeruginosa PAO1 strains inactivated or (over)expressing dipA, dipA-NoGAF, GAFonly, or dipA harboring an alanine substitution in either one of the EAL motifs. The swarming diameter was recorded following 24 h of growth on M8 agar. Insets above the graph are representative images showing swarming motility of selected strains. (C) Initial attachment of the P. aeruginosa PAO1, ΔdipA, and PAO1/pMJT-dipA strains following 6 h of growth using the microtiter plate dish assay and crystal violet staining. (D) Psl polysaccharide levels relative to the PAO1 parental strain as determined using anti-Psl dot blot analysis. (E) pelA and pslA are not differentially expressed in PAO1 and PA14 strains inactivated in or overexpressing dipA compared to the parental strains, as determined qRT-PCR analysis. *, significantly different from PAO1 (P < 0.05), as determined by ANOVA and SigmaStat.