Megan B. Turner

Ionic liquid salt-induced inactivation and unfolding of cellulase from Trichoderma reesei

The potential for performing cellulase-catalyzed reactions on cellulose dissolved in 1-butyl-3-methylimidazolium chloride ([bmim]Cl) has been investigated. We have carried out a systematic study on the irreversible solvent and ionic strength-induced inactivation and unfolding of cellulase from Trichoderma reesei (E.C. #3.2.1.4). Experiments, varying both cellulase and IL solvent concentrations, have indicated that [bmim]Cl, and several other ILs, as well as dimethylacetamide–LiCl (a well-known solvent system for cellulose), inactivate cellulase under these conditions. Despite cellulase inactivity, results obtained from this study led to valuable insights into the requirements necessary for enzyme activity in IL systems. Enzyme stability was determined during urea, NaCl, and [bmim]Cl-induced denaturation observed through fluorescence spectroscopy. Protein stability of a PEG-supported cellulase in [bmim]Cl solution was investigated and increased stability/activity of the PEG-supported cellulase in both the [bmim]Cl and citrate buffer solutions were detected.

New ionic liquids containing an appended hydroxyl functionality from the atom-efficient, one-pot reaction of 1-methylimidazole and acid with propylene oxide

New ionic liquids containing (2-hydroxypropyl)-functionalized imidazolium cations have been synthesized by the atom-efficient, room temperature reaction of 1-methylimidazole with acid and propylene oxide; the acid providing the anionic component of the resultant ionic liquids. The incorporation of the secondary hydroxyl-functionality in the cation causes some interesting modifications to the behavior of these ionic liquids, increasing hydrophilicity and resulting in the unprecedented formation of liquid–liquid biphases with acetone. The single crystal structure of 1-(2-hydroxypropyl)-3-methylimidazolium tetraphenylborate, prepared by metathesis of the corresponding chloride-containing ionic liquid, has also been determined.