FIG 3 .

PQS induces RBC membrane curvature. Compounds were added to washed RBCs and observed using light microscopy after 30 min. (A) RBCs treated with DMSO only. (B) RBCs treated with 5 µM PQS; white arrows point to echinocytes (spicule-containing cells). (C) RBCs were exposed to a series of compounds to assess the impact of chemical structure on the ability to promote membrane curvature. The bars represent the average number of echinocytes per 100 cells. Averages were calculated from at least three independent measurements (≥6,800 total cells). Error bars show the standard errors of the means. Asterisks represent statistically significant differences from PQS (5 µM) using a one-tailed t test. *, P < 0.05; ***, P ≤ 0.0001. HHQ, 2-heptyl-4-quinolone.