Western immunoblot showing FpvA production in P. aeruginosa strains K767 (lane 1), K1660 (lane 2), K1660(pRK415) (lane 3), K1660(pJSS4) (lane 4), K1661 (lane 5), K1660(pJSS5) (lane 6), and K1662 (lane 7) grown in iron-limited succinate minimal medium. Whole-cell extracts were prepared from stationary-phase cells and probed with antibodies to FpvA following electrophoresis and electroblotting as described in Materials and Methods.