Mechanism of Leakage in Phosphatidylserine-Containing Membranes by Melittin

Abstract Phosphatidylserine (PS) is an important apoptotic-cell surface signal that exists in bacterial and cancer cells. The mechanism by which melittin interacts with the PS membrane remains unclear. Here, we revealed this mechanism by using a dual-channel fluorescence microscope to observe the concentration-dependent process of pore formation in giant unilamellar vesicles (GUVs) that were exposed to melittin solution. We found that unsaturated PS membranes differed significantly from saturated PS membranes in different phases. This study provides a reference for research and development of anticancer drugs.