Redox biocatalysis in ionic liquids

I&EC 117

Heather C Stubley, hcs110@york.ac.uk, Department of Biology, University of York, PO Box 373, York, YO10 3LR, United Kingdom, Adam J Walker, adam.walker@bioniqs.com, Bioniqs, Biocentre, York Science Park, York, YO10 5DG, United Kingdom, and Neil C Bruce, CNAP, Department of Biology, University of York, Heslington, York, YO10 5DD, United Kingdom.
Enzymes are remarkable catalysts, ideal for organic synthesis. In vivo enzymatic reactions occur in water, but problems arise due to poor substrate solubility and proteolysis. Studying enzymes in non-aqueous systems provides novel information about enzyme reactions and allow impossible or marginal reactions to occur. Studies in organic solvents show enzymes can be active in non-aqueous solvents. Ionic liquids have great potential for enzyme catalysis, they are powerful solvents that are liquid at room temperature and composed only of ions. They lack vapour pressure, are generally polar with varying physical properties. Their characteristics arise through the asymmetrical interaction of the cation and anion. They can be tailored by altering the ion composition, allowing the solvent to be designed around an enzyme. This study focuses on activity and stability of alcohol dehydrogenase (ADH) in ionic liquids, structure of ADH in ionic liquids and effect of water content upon enzyme structure and activity.