Figure 3.

ITC heat traces of POPC/POPG (3:1) LUVs injected into MPX solution. (A) Calorimetric heat traces of lipid-into-peptide titrations conducted at 15°C, 20°C, and 25°C (38 × 1 μL 18.9 mM POPC/POPG (1:3) injected into 204 μL 100 μM MPX). (B and C) Integrated heat trace (Q) (B) and accumulated molar heat (Q_acc/n_cell) (C) are shown as a function of the lipid/peptide ratio (L/P). The threshold (L/P)^∗ at which pores cease to exist (or are formed if titrated oppositely) at 20°C, is indicated by a dashed vertical line in C. The pore formation energy is denoted by Q_pore. The integrated heat of injection (Q_acc) in C is normalized with respect to the moles of peptide in the ITC cell (n_cell). Lines serve to guide the eye.