Fig. 5. Internalization of particles and fluid phase in lvsA mutant cells. Wild-type (filled circles) or lvsA mutant cells (open circles) were incubated for various times in the presence of fluorescent latex beads (A), rhodamine-labeled Klebsiella aerogenes (B) or FITC-dextran (C). The amount of internalized fluorescence was analyzed using a fluorescent-activated cell sorter (FACS). The results are expressed as a percentage of the internalization by wild-type cells after 90 minutes. Insert in (A), to check for fluorescent latex beads internalization at early time-points, cells were incubated with beads for various times up to 20 minutes, then fixed and analyzed by FACS. (D) To measure recycling of internalized fluid phase to the extracellular medium, cells were allowed to internalize FITC-dextran for 1 hour, then washed and incubated for the indicated times. The fluorescence remaining in the cells was then analyzed by FACS.