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Show Properties of Encapsulated Proteins in Reverse Micelles Mark Ogilvie and Peter Flynn Department of Chemistry Membrane proteins are important in most all biological processes and implicated in many diseases. Nearly one-third of all proteins are membrane proteins, and greater than 80% of all drugs target membrane proteins. Yet, there are only 225 solved membrane protein structures out of 39,969 solved protein stuctures in the RCBS protein data bank as of November 2006 (only 0.56% are membrane proteins). Encapsulation of proteins in reverse micelles using surfactants may lend itself well to the study of membrane proteins using solution Nuclear Magnetic Resonance (NMR) techniques. Surfactants serve a two fold purpose with cell membrane proteins: they mimic a lipid bilayer so native protein structure is retained and surfactants allow use of less viscous solvents. Inside the reverse micelle, the protein may be in its native environment of water, pH, salt content, etc. while outside the reverse micelle a less viscous solvent such as pentane may be used. A decrease in solvent viscosity leads to an increase in tumbling (i.e. the macromolecules reorient slowly in solution) and subsequent increase in sensitivity in NMR experimentation. The goal of the project is to establish encapsulation systems that optimize the effectiveness of this method. NaAOT (sodium bis(2-ethylhexyl)sulfosuccinate) is historically the more commonly used surfactant in these types of studies. Although this surfactant has generally favorable properties, new forms e.g., Mg2+, K+, etc., and possible other salts may possess superior characteristics. In an effort to explore the possibility of generating an improved surfactant, Na+ in NaAOT was exchanged with Mg2+ and K+. Results indicated that the Mg2+ form of AOT has enhanced water holding characteristics, whereas the K+ salt has decreased capacity. Furture studies will thus focus on refinement of the favorable water-carrying capacity of Mg(AOT)2 and testing that system using a wide variety of buffers. This research is supported with funding from The University of Utah, Seed Grant Award. Mark Ogilvie is supported by funding from The University of Utah, Undergraduate Research Opportunities Program. |