Table 2. Range and specificity of inhibition and phagocytosis.
% of structures at the aggregate stage | Phagocytosis of prey cells | ||
buffer | D. caveatum | by D. caveatum | |
D. aureostipes | 37 (28) | 83 (30) | + |
D. fasciculatum | 24 (18) | 70 (26) | + |
D. mucoroides | 14 (15) | 100 (0) | + |
D. rosarium | 4 (7) | 97 (6) | + |
Four additional Dictyostelid species were tested according to the same protocol as in Figure 4A. The table indicates the number of aggregates for each species as a percentage of the total number of developmental stages observed on filters after 24 hours of incubation (average (standard deviation)), as illustrated in Figure 5. In the controls, development at 24 h has passed the aggregate stage, while in the presence of D. caveatum (108 cells/mL inside the dialysis membrane) development is blocked at this stage (compare first two columns). The ability of D. caveatum to phagocytose ameobae of these species, as assessed by live cell microscopy, is also indicated: all these Dictyostelid species are ingested by D. caveatum in the same manner as D. discoideum (Movie S1D).