Effects of surfactin on membrane models displaying lipid phase separation

► At low conc., surfactin (SF) binds to the boundary between gel and fluid domains. ► At conc. close to CMC, SF induces a high ordering effect of the bilayer. ► At high conc., SF destabilizes totally the bilayer with formation of large particles. ► SF interacts both with the membrane polar heads and the acyl chain region.