Figure 1.

Use of the D. discoideum social development assay to evaluate K. pneumoniae virulence. (A) Main stages of the D. discoideum social cycle, which culminates with the formation of the fruiting bodies. The scheme was adapted from Fey et al. (2007). (B) Micrographs of the social cycle progression when feeding amoeba with different K. pneumoniae strains or with K. aerogenes DBS0305928 (control). Scale bar, 100 μm. (C) Semi-quantitative assessment of the social cycle progression in presence of different Klebsiella strains using several replicates. The symbols represent the mean of six independent experiments and the error bars show the standard deviation. The details on scoring criteria can be found in the Materials and Methods section.