Enhanced Activity and Enantioselectivity of a Hyperthermophilic Esterase from Archaeon Aeropyrum pernix K1 by Acetone Treatment

To improve the activity and enantioselectivity of hyperthermophilic archaeon Aeropyrum pernix K1 esterase (APE1547) and its mutants, they were purified by acetone-treated method. It was found that the acetone treatment not only caused APE1547 and its mutants to display higher activity and enantioselectivity but also saved more than 90% of time spent in purifying them by Ni-chelating column. In hydrolysis of p-nitrophenyl caprylate, the acetone-treated APE1547 and mutant A containing the following substitutions R11G, L36P, V225A, I551L, and A564T showed 5.7- and 6.9-fold active increase, respectively. In the resolution of 2-octanol acetate, the acetone-treated mutant A had a 9-fold enantioselective increase relative to that purified by Ni-chelating column. In addition, the impact of pH, temperature, and chemical reagents on activity of APE1547 and mutant A was discussed in this paper.