Incorporation of Reaction Center Proteins into Tethered Lipid Vesicles

INCORPORATION of Reaction Center Proteins into Tethered Lipid Vesicles

The ubiquity integral membrane proteins and their importance in cellular processes, particularly signaling and transport, have motivated a wide range functional and structural studies. However, it has proven to be very difficult to incorporate functional and laterally mobile membrane proteins into supported lipid bilayers, which allow experimental access to and control over bilayer components. This difficulty presumably is due to the close proximity of the solid support surface to the bilayer.

We here demonstrate that the reaction center, an integral membrane protein from purple photosynthetic bacteria, is successfully reconstituted into lipid vesicles and tethered via complementary DNA oligonucleotide-lipid conjugates to a planar lipid bilayer. Using dye-labeled proteins and lipids, the presence of both protein and lipid in individual tethered vesicles is easily confirmed by fluorescence microscopy. The proteoliposomes are mobile on the surface, demonstrating that the tethered vesicle system may be used to study membrane protein function and interaction in a native-like lipid environment.

Other research interests

Covalent modification of the reaction center for incorporation of probes that can report protein properties/function (electron transfer) e.g.
–measurement of the electric fields in the reaction center using vibrational probes
–protein dynamics as a function of charge separation using spin labels

Non-research interests

Classical music performance (violin/viola, chamber music), science policy, hiking/tennis/swimming