ORGN 386 |
| Controlled communication between cells is vital for the function of multi-cellular organisms. The influx and efflux of species (ions and small molecules) into and out of a cell is often facilitated by channel-forming proteins in the membrane, and is carefully controlled. This control of release is a key aspect of natural systems that biomimetic approaches to membrane transport have so far found difficult to replicate. We wish to develop novel synthetic ligand-gated channels that form through metal ion-induced self-assembly in a phospholipid bilayer. Removal of the metal ion causes dissociation of the complex and collapse of the channel. The walls of the channel are composed of cholic acid functionalised with binding headgroups (e.g isonicotinyl). These headgroups bind to palladium(II) to form a membrane-spanning dimeric complex. Such membrane-spanning bischolates are believed to self-assemble further into multimeric pores within phospholipid bilayers, which allow the passage of alkali metal ions across the membrane. The synthesis of the Pd(II)-binding cholates is presented, followed by alkali metal ion transport assays and further studies investigating the behaviour of our channels. Addition of a strong Pd(II) complexing agent dissembled the complex, halting ion transport. We also present a new synthesis of a covalently-linked dimer which we are now elaborating to form novel compounds for vesicle-to-vesicle ion transport.
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Heterocycles and Aromatics, Molecular Recognition and Self Assembly
8:00 PM-10:00 PM, Tuesday, April 8, 2008 Morial Convention Center -- Hall A, Poster
Sci-Mix
Division of Organic Chemistry |
