Single-Molecule FRET Reveals Transport Mechanism of ABC Transporters

The cell is the basic membrane-bound unit that contains the fundamental molecules of life, of which all living things are composed. The wall of the cell is something composed by, for example, peptide glycan layer which is not simply a passive barrier, but a major interface between the cell cytoplasm with the exterior. Exchanging essential compounds and wasteful molecules through the membrane requires transporters. Small molecules can potentially pass through the lipid bilayer wall by diffusion and osmosis mechanism, where molecules pass through the pores built by the phospholipid layer. However, the majority of deliverance is accomplished by variety of membrane-affiliated proteins. These proteins distinguish the nutrients to be taken, wasteful products to be excreted or directed between the inside and outside the cell. In this chapter, I introduce the basic features of the biological membrane, protein transporters, and the technique used to examine transport phenomenon. The thesis reveals dynamic information of substrate-binding and transport as well as overpasses the limitation of established structure determinations.