Biological Supermolecules-Learning from Nature

2 Controlling Material Transport - Ion Channels Ion channels maintain two different ion compositions outside and inside a cell via active transport. The immobilization of appropriately designed molecules in a lipid bilayer membrane leads to the formation of artificial ion channels. 

3 Information Conversion and Amplification - Signal Transduction When an extracellular signal is recognized by a receptor on a cell membrane, the G-protein activates the enzyme inside the cell. The activation of an enzyme by external chemicals can be mimicked using a system consisting of an artificial receptor and an enzyme immobilized on an artificial lipid bilayer membrane. 

4 Energy Conversion - Photosynthesis During the process of photosynthesis, a well-organized dye array in the cell membrane accomplishes pho-toinduced charge separation that eventually leads to ATP synthesis. This system has been mimicked by immobilizing a fimctional dye molecule and ATP synthase in a lipid bilayer membrane. 

5 Material Conversion - Natural and Artificial Enzymes Enzymes perform highly selective and highly efficient molecular conversion based on sophisticated three-dimensional arrangements of amino acids. Artificial enzyme mimics can be constructed using cyclodextrins and Hpid bilayer membranes. 

6 Cleaving Genes - Restriction Enzymes Restriction enzymes can cleave nucleic acids at specific sequences. Artificial restriction enzymes can be prepared by combining oligo(nucleic acids) and supramolecular catalytic sites. 

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