B. bronchiseptica LapG and LapD complement their respective P. fluorescens mutations.

(A) Biofilm formation by the P. fluorescens ΔlapG mutant (PfΔlapG) carrying plasmids expressing the B. bronchiseptica or P. fluorescens lapG genes was determined by the CV biofilm assay. (B) Cell surface levels of LapA as measured by dot blot. Shown is a representative dot blot assay (top) and quantification of the pixel density (n = 6 ± SD; bottom) to assess the level of cell surface LapA of the P. fluorescens strains expressing LapG or LapD, as well as indicated control strains. *, ** or *** indicate significant differences between strains, p<0.05, p<0.01 and p<0.005 respectively. (C) Biofilm formation by the P. fluorescens ΔlapD mutant (PfΔlapD) carrying plasmids expressing the B. bronchiseptica or P. fluorescens lapD genes was determined by the CV biofilm assay. *, ** or *** indicate significant differences between strains, p<0.05, p<0.01 and p<0.005 respectively.