FIG. 5.

CAS reactivity of an L. pneumophila serogroup 1 pigment mutant. Strains Philadelphia-1 (●); JR32, a restriction mutant of Philadelphia-1 (■); and JR32-1, a pigment mutant of JR32 (▴), were grown in BYE to an OD₆₆₀ of 1.1, washed, and then inoculated into iron-depleted CDM. Over the next 2 days, the growth (top) and CAS reactivity (bottom) of the cultures were recorded. For reference, the CAS reactivity of the CDM blank is included (◊) in the lower panel. The values presented represent the means and standard deviations from duplicate cultures. The slightly reduced level of CAS reactivity seen in the JR32-1 culture was not observed in either of the two additional experiments that were done.