(A) Plot of stabilizing effect (defined as the ELIC pentamer peak height with phospholipid relative to control after heating) versus phospholipid concentration (n = 3, ± SD; EC50 = 52 μM, Hill n = 1.7). Inset shows size exclusion chromatography (SEC) profile in absorbance units of the ELIC pentamer treated at 4°C, 32°C, and 32°C with 100 μM POPG. (B) Top: Representative ELIC current responses to 30 mM cysteamine in 25 mole% POPG liposomes. Bottom: Normalized plots of peak current responses of ELIC to cysteamine in giant liposomes with varying mole% POPG (n = 3–5, ± SD). Data are fit to Hill equation with n = 2. (C) Representative ELIC currents in response to 30 mM cysteamine in liposomes with varying mole% POPG. (D) Left: ELIC currents 20 s after application of 30 mM cysteamine normalized to peak response at varying mole% POPG (n = 4–5, ± SD, **p<0.01). Right: Weighted tau (time constants) of ELIC desensitization at varying mole% POPG (n = 3–5, ± SD, **p<0.01, *p<0.05). (E) Representative fluorescence-quench time courses from sequential mixing stopped-flow experiments of ELIC in POPC liposomes or 2:1:1 POPC:POPE:POPG liposomes. Proteoliposomes were mixed with no cysteamine (cnt) or 5 mM cysteamine with a 0.1, 5, and 25 s delay prior to mixing with Tl+. (F) Rate constants extracted from quench kinetics as shown in (E) as a function of the incubation time with cysteamine. Data are fit with a double exponential yielding activation and desensitization time constants (n = 3, ± SD).