Figure 5.

Influence of cholesterol and PL headgroup on the lateral segregation. (A) shows the tPA fluorescence lifetimes (representative data) as a function of PSM content at different cholesterol concentrations together with POPC at 23°C. The PSM concentration at which these trendlines change slope defines the PSM content at which the lateral segregation was initiated. For the POPC-based bilayers, these are summarized in (B) (values are averages + SD with n ≥ 3.). (C) shows representative lifetime components observed in different ternary mixtures of PLPE, PSM, and 5 mol% cholesterol. The impact of different headgroups in the unsaturated lipids on the formation of the gel and l_o phases (and the difference between these two) by PSM at 23°C is quantified in (D). These values are averages + SD with n ≥ 3. To see this figure in color, go online.