Figure 6.

Deletion of sprP increases pyoverdine production by Pseudomonas aeruginosa. Strains were incubated at 37°C until cell growth reached an OD_580nm of 2.5 and pyoverdine in cell-free culture supernatants was determined by absorbance at 403 nm (Meyer and Abdallah 1978). Pyoverdine production is indicated as pyoverdine absorbance (A_403nm) per cell density (OD_580 nm). Error bars indicate standard deviation calculated from biological triplicates. Cuvettes containing culture supernatants are shown underneath the diagram. wt = P. aeruginosa PAO1, ΔsprP = P. aeruginosa ΔsprP harboring either ev = empty vector or sprP = plasmid pBBRSP.