Fig 6. P. aeruginosa PilU functions in a PilT-dependent manner.
(A) Strains encoding arabinose-inducible versions of P. aeruginosa pilT (araC PBAD-pilT[Pa]; TnpilT[Pa]) and pilU (araC PBAD-pilU[Pa]; TnpilU[Pa]), within an ectopically integrated transposon, were tested for their ability to complement the enhanced motility phenotype of various backgrounds, in the absence (- Ara) and presence (+ Ara) of induction, as indicated. Surface motility was determined on soft LB agar plates. The swarming diameter (cm) is the mean of three repeats (±S.D.). A flagellin-deficient (ΔflaA) non-motile strain was used as a negative control. (B) Chitin-dependent transformation assay testing the ability of TnpilT[Pa] and TnpilU[Pa] to complement the transformation defect of various backgrounds. Transformation frequencies are the mean of three repeats (+S.D.). < d.l., below detection limit. All strains were cultured on chitin in the presence of arabinose. The corresponding parental strains without a transposon served as negative controls.