Investigation of polylysine-dipalmitoylphosphatidylglycerol interactions in model membranes

The effect of poly(L-lysine) on dipalmitoylphosphatidylglycerol bilayers has been studied by Raman and infrared spectroscopies, small-angle X-ray diffraction, and carboxyfluorescein escape experiments. The polypeptide is shown to induce a stabilization of the bilayer detected by the increase of interchain vibrational coupling and a slight decrease of the overall disorder. In addition, long polylysine (Mr 150,000) induces a positive shift of the...