Control of Membrane Fusion Mechanism by Lipid Composition: Predictions from Ensemble Molecular Dynamics
Figure 6
Dependence of Stalk Formation on Fraction POPC in Outer Leaflet
Plotted are average times for reaction of unfused vesicles to initiate a hemifusion stalk, as determined by analysis of simulations with differing inner and outer leaflet compositions. Stalk formation times are plotted for both 15 nm vesicles (diamonds) and 19 nm vesicles (triangles); single-exponential fits to the data are shown (r2 = 0.88). Linear fits to the data yield r2 values of 0.67 (0.79 with the 0% POPC datapoint omitted) and 0.81, respectively. Initial stalk formation is assessed here by mixing of >10 lipids between vesicle outer leaflets.