Structural characterization of LLO assemblies by HS-AFM.

a) HS-AFM topography image of LLO oligomers on a DOPC:Cholesterol 4:1 mol:mol membrane observed in 20mM MES, pH5.6, 100mM NaCl, 5mM MgCl₂, with 500nM LLO. The LLO forms arc-shaped assemblies. Inset: LLO arcs imaged at high resolution (time-averaged over 3 consecutive frames) b) Height histogram distributions of pre-pore (red) and pore (blue) complexes. The Gaussian fits indicate heights of 11.1±0.5nm (n = 120), and 7.3±0.2nm (n = 160) for the pre-pore and pore oligomers, respectively. c) The oligomers form assemblies with rather well preserved arc radius (red) of 31±3nm (n = 120) and arc length (blue) of 51±6nm (n = 120). d) The individual LLO subunits displayed dimensions of a minor axis along the arc (red) of 2.5±0.2nm (n = 120) and major axis across the arc (blue) of 7.0±0.3nm (n = 160).