Figure 1.

High Gdm⁺ permeability in infected but not uninfected RBCs. (a) Osmotic lysis kinetics for infected erythrocytes in Gdm-Cl or sorbitol at 37°C (top two traces). Notice the faster kinetics in Gdm-Cl. Uninfected cells do not lyse in Gdm-Cl (bottom trace). Inset shows the structure of Gdm⁺, which has a net +1 charge distributed amongst three primary amines. (b and c) Osmotic lysis kinetics for infected cells in Gdm-Cl with 0, 200, or 2000 μM furosemide (top to bottom traces, resp.). 200 μM furosemide produces incomplete inhibition at 37°C but is more effective at 20°C (panels b and c, resp.), suggesting that Gdm⁺ is an R+ solute.