Biotechnological Application of Membrane Proteins Reconstituted Into Vesicular and Planar Lipid Bilayers
Proteins and lipids are the building blocks of biological membranes. In the past and at present, only the lipids in the form of bilayers, vesicles, and thin films found/find applications in technology. However, the membrane proteins are responsible for most of the vital processes accomplished by membranes. These proteins, which are in part or completely embedded in the lipid matrix mainly via helical amino acid regions, act as pores (channels), pumps, and transport systems for ions and nutriments. Furthermore, they are very selective receptors for hormones, neurotransmitter, drugs, medicine, and they mediate specific cell-cell recognition. Biological membranes can be regarded as the largest and most active organ in a living organism. They are the site of many vital processes for life. Photosynthesis and oxidative phosphorylation, the two most important energy conversion processes in biological systems as well as sensory transduction are carried out by membranes, i.e., by the proteins residing in the membrane. Therefore, it can be expected that in the near future membrane proteins will gain great importance in biotechnology. In the following, the putative capacity of membrane proteins to serve as biosensor, biochip, and bioconverter of energy will be discussed by referring to the light-driven proton pump bacteriorhodopsin.
KeywordsLipid Vesicle Rotational Diffusion Planar Lipid Bilayer Purple Membrane Lipid Phase Transition
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