Polylysine induces pH-dependent fusion of acidic phospholipid vesicles: a model for polycation-induced fusion

Polylysine induced aggregation and fusion of negatively charged small unilamellar phosphatidylcholine vesicles containing at least 10% anionic lipid. Aggregation was followed by absorbance changes and fusion was assayed both by electron microscopy and by fluorescence energy transfer between lipid probes. A method for preparing asymmetric vesicles, where the fluorescent probes were present only in the inner monolayer of the vesicle membrane, was...