Biofunctional Assemblies at Lipid Interfaces through Recombinant Spherical Bacterial Protein

A novel strategy to construct biomimetic assemblies of bio macromolecules on supported membranes is presented. It is based on the anchoring of a 15 nm ball-like recombinant protein, lumazine synthase, on a phospholipid membrane. These proteins have functional groups pointing in solution. They are coupled to phospholipids in solution exhibiting different functional headgroups like biotin and Ni chelator complexes. In this feasibility study we probe the adsorption dynamics of LuSy molecules on phospholipid membranes functionalised with different key-lock like binding mechanisms. The density of adsorbed protein is followed by neutron reflectivity experiments. The influence on the adsorption process of the concentration of a competing inhibiting lipopolymer (phospholipid with polyethylene-glycol headgroup called PEG) at the interface was also measured.