FIG 7.

Localization and shape of the wild-type and T2SS mutant L. pneumophila phagosomes. A. castellanii amoebae were infected with GFP-positive wild-type strain 130b (WT) or lspF mutant NU275 (lspF), and z-stack images were generated every 30 min and then converted into 3D objects. (A) Quantification of the localization of GFP-positive phagosomes to the amoebal contractile vacuole following infection with wild-type (WT) or lspF mutant bacteria. (B) Distinct phagosome shapes (defined as a to f) were observed and quantitated as a percentage of the total phagosomes over the course of the infection, as displayed in the top panel for the wild type and the mutant. Representative images of these shapes are presented in the lower panel (scale bar, 5 μm), showing GFP-expressing wild-type phagosomes localizing to and then enveloping the contractile vacuole (demarcated by yellow dashed lines) before filling the entire amoebal cell. The data presented in panels A and B are pooled from three replicate experiments.