His-tagged Horse Liver Alcohol Dehydrogenase: Immobilization and application in the bio-based enantioselective synthesis of (S)-arylpropanols

The novel histidine-tagged Horse Liver Alcohol Dehydrogenase (His-HLADH-EE) was successfully purified and covalently immobilized onto a solid support in a one-step procedure through a metal-directed technique. A full characterization of the immobilized enzyme was carried out. Effects of pH, temperature and organic co-solvents were deeply investigated and they showed a shift in the optimum pH with respect to the free form as well as increased stability to temperature and solvents. The immobilized His-HLADH-EE proved to be effective as catalyst in the reduction of aliphatic and aromatic aldehydes. Application of the free and immobilized His-HLADH-EE to the chemo-enzymatic synthesis of (S)-Profenols demonstrated enhanced enantioselectivity and high reusability of the immobilized form. The achievement of a robust and effective immobilization of an alcohol dehydrogenase substantiated the use of biocatalytic reduction in the synthesis of primary alcohols and valuable chiral intermediates especially for pharmaceutical industries. (C) 2013 Elsevier Ltd. All rights reserved.