A modular platform for one-step assembly of multi-component membrane systems by fusion of charged proteoliposomes

An important goal in synthetic biology is the assembly of biomimetic cell-like structures, which combine multiple biological components in synthetic lipid vesicles. A key limiting assembly step is the incorporation of membrane proteins into the lipid bilayer of the vesicles. Here we present a simple method for delivery of membrane proteins into a lipid bilayer within 5 min. Fusogenic proteoliposomes, containing charged lipids and membrane proteins, fuse with oppositely charged bilayers, with no requirement for detergent or fusion-promoting proteins, and deliver large, fragile membrane protein complexes into the target bilayers. We demonstrate the feasibility of our method by assembling a minimal electron transport chain capable of adenosine triphosphate (ATP) synthesis, combining Escherichia coli F 1 F o ATP-synthase and the primary proton pump bo 3 -oxidase, into synthetic lipid vesicles with sizes ranging from 100 nm to ∼10 μm. This provides a platform for the combination of multiple sets of membrane protein complexes into cell-like artificial structures. Assembling multiple biological components into synthetic lipid vesicles is a limiting step in the manufacture of biomimetic cell-like structures. Here the authors use fusogenic proteoliposomes of opposite charge for fast assembly of a minimal electron transport chain consisting of F 1 F 0 ATP-synthase and the proton pump bo 3 -oxidase.