A Comparative Study of α-Hemolysin Expression in Supported Lipid Bilayers of Synthetic and Enriched Complex Bacterial Lipid

The purpose of this short communication was to examine whether the formation of a supported lipid bilayer (SLB) made with purely synthetic lipid or with Escherichia coli complex lipid may have any influence on the production and incorporation of the transmembrane protein α-hemolysin from Staphylococcus. Different molar ratio of E. coli total extract lipid and synthetic 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) were used to prepare SLB, which were characterized by combination of quartz crystal microbalance with dissipation monitoring (QCM-D), fluorescence recovery after photobleaching (FRAP), and atomic force microscopy (AFM). It was found that a 68:32 molar ratio was optimal to produce a SLB mimicking a bacterial lipid membrane. Comparing this later SLB with a purely synthetic SLB (100 % POPC) as receptacle for expression of the Staphylococcus α-hemolysin fused to eGFP by a cell-free expression system (CFES), we showed that both production and incorporation of this membrane protein was very similar. © 2014 Springer Science+Business Media New York.