They are thus ideal biosensors, but until now were difficult to access in the lab. However, Max Planck scientists have now managed to incorporate in-vitro synthesized membrane proteins directly into artificial lipid membranes (Angewandte Chemie, International Edition, January 15, 2007).
The senses of living organisms function using various mechanisms, among other things utilizing membrane proteins as receptors. Researchers at the Max Planck Institute for Polymer Research and the Max Planck Institute of Biochemistry have now succeeded in creating biosensors by incorporating such proteins into artificial structures. The membrane proteins are synthesized in-vitro directly from the genetic information introduced to the cell extract.
Previous attempts to create biosensors from membrane proteins failed due to an idiosyncrasy of these proteins: they are not water soluble. In the past, researchers tried to remove the proteins from their biological membranes by solubilising the latter using detergents. However, this destroys the natural folding structure of the protein membranes, which is precisely what makes the proteins so special. "We quickly realized how difficult it is to isolate such membrane proteins. Neither we, nor other research groups, were able to work with them using conventional methods," explains Dr. Eva-Kathrin Sinner of the Max Planck Institute for Polymer Research in Mainz .
Yet the Max Planck researchers found a