Enhanced production of D-psicose from D-fructose by a redox-driven multi-enzyme cascade system.

D-Psicose, a new-generation sugar substitute, has been enzymatically synthesized through D-fructose isomerization. However, isomerization often causes low yields due to unfavorable thermodynamic equilibria, which limited its further industrial application. In this study, we present a redox-driven multi-enzyme cascade, two-step biotransformation system to produce D-psicose from D-fructose.

Protein Engineering and Homologous Expression of Serratia marcescens Lipase for Efficient Synthesis of a Pharmaceutically Relevant Chiral Epoxyester.

The lipase isolated from Serratia marcescens (LipA) is a useful biocatalyst for kinetic resolution of a pharmaceutically relevant epoxyester, (±)-3-(4'-methoxyphenyl) glycidic acid methyl ester [(±)-MPGM], to afford optically pure (-)-MPGM, a key intermediate for the synthesis of diltiazem hydrochloride. Two mutants, LipA and LipA, were identified from the combinatorial saturation mutation library of 14 amino acid residues lining the substrate-binding pocket. LipA, LipA, and their combination LipA showed 2.

Engineering 7β-Hydroxysteroid Dehydrogenase for Enhanced Ursodeoxycholic Acid Production by Multiobjective Directed Evolution.

Ursodeoxycholic acid (UDCA) is the main active ingredient of natural bear bile powder with multiple pharmacological functions. 7β-Hydroxysteroid dehydrogenase (HSDH) is a key biocatalyst for the synthesis of UDCA. However, all the 7β-HSDHs reported commonly suffer from poor activity and thermostability, resulting in limited productivity of UDCA.