FIG. 6.

Fpp1 production by F. psychrophilum during growth. (A) The bacterium was grown at 12°C in NBF medium, and at different times (arrow 1, 28 h; arrow 2, 48 h; arrow 3, 52 h; arrow 4, 90 h; arrow 5, 96 h) Fpp1 was detected by Western blotting. Growth was monitored by determining culture absorbance at 525 nm (Abs 525 nm). (B) The bacterium was grown at 12°C in NB, and in the middle of the exponential phase (lane 2) or in the stationary phase (lane 3) 10 mM CaCl₂ was added to the cultures. In both cases, incubation was continued for two additional days, and Fpp1 was detected by Western blotting. Lane 1 contained with an NB culture used as a negative control. (C) The microorganism was grown at 12°C in NBF medium for 2 days (stationary-phase culture), and then cells were washed by centrifugation and resuspended in NB (lane 2) or NBF medium (lane 1). Incubation was continued for two additional days, and samples for immunoblot analysis were obtained as described in Materials and Methods. All of the immunoblot experiments were carried out three times.