A number of extremophilic enzymes functioning at the temperature of 100oC or above it are found in nature. Only few such enzymes have been created by protein engineering from less stable enzymes. The structural parameters and interactions that determine the enzyme's ability to function at extreme conditions were studied by planning mutations to the relevant positions in the protein structure. High pressure is one of the extreme conditions inactivating enzymes, although in limited range it may also increase enzyme activity (Mombelli et al., 2002; Meersman et al., 2006). We studied the pressure stability of disulphide bridge mutants of Trichoderma reesei XYNII (Turunen et al., 2001; Janis et al., 2004, 2008) at high pressure. Ionic liquids, especially hydrophobic ones, are known to stabilize enzymes, including cellulases. The ionic liquids that dissolve lignocellulose are highly destabilizing for the enzymes (Zhao et al., 2010; Lozano et al., 2011; Bose et al., 2012). We studied the effect of the stabilization of extremophilic Dictyglomus thermophilum GH11 xylanase against high temperature and in the presence of a biomass-dissolving ionic liquid, 1-ethyl-3-methylimidazolium acetate ([emim]OAc). This research generated information that can be useful in developing new enzymes for the conversion of lignocellulose to fuel alcohols and chemicals.

Engineering the industrial enzymes to function at extreme conditions

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.