FIG. 1.

SOD activity in planktonic cells cultured in TSB. Cell extracts (50 μg of protein per lane) of each strain were prepared at different time points corresponding to different growth stages, 6 h (mid-log phase) and 10 h (early stationary phase). SOD activity stains of wild-type strain PAO1 cultured in TSB (A), PAO1 in TSB amended with the iron-specific chelator 2,2-dipyridyl (B), and the lasI mutant PAO-JP1 in TSB amended with the iron-specific chelator 2,2-dipyridyl (C) were prepared as described in Materials and Methods. Results are of one of three independent experiments demonstrating this response.