Building a Better Microreactor: Enzyme Catalysis in AOT/Bile Salt Reversed Micelles

摘要

The goal of this project is to design efficient reversed micellar microreactors for enzymatic detoxification of chemical agents. Enzymes are solubilized in aqueous pools by a detergent layer that serves as an interface to the bulk organic solvent. We have shown that trihydroxy bile salts modify the interfacial properties of AOT reversed micelles, thereby affecting the reversed micellar structure, the biological activity of entrapped enzymes and the transport of substrate and products across the micellar interface. Studies of commercial enzyme show that the mechanisms by which bile salts affect enzymatic activity and stability in AOT reversed micelles vary from protein to protein, but in all cases, the effects were positive - bile salts were found to increase enzymatic activity and stability. Small angle neutron scattering (SANS) was used to estimate the dimensions of the various aggregates with and without enzyme. The novel microreactor will be applied to an organophosphorus acid anhydrolase (OPAA-2), which is of interest to the Army for its ability to detoxify acetylcholinesterase inhibitors found in chemical warfare agents. We will study the structure and kinetics of OPAA-2 in AOT reversed micelles with bile salts, in order to design an optimal microreactor for detoxification of organophosphorus compounds.