Applying a thermostable and organic solvent tolerant ene-reductase for the asymmetric reduction of (R)-carvone.

Applying a thermostable and organic solvent tolerant ene-reductase for the asymmetric reduction of (R)-carvone.
Chembiochem. 2019 Nov 06;:
Authors: Tischler D, Gädke E, Eggerichs D, Gomez Baraibar A, Mügge C, Scholtissek A, Paul CE
Abstract
Ene-reductases allow regio- and stereoselective reduction of activated C=C double bonds at the expense of nicotinamide adenine dinucleotide cofactors (NAD(P)H). Biological NAD(P)H can be replaced by synthetic mimics to facilitate enzyme screening and process optimization. The ene-reductase FOYE-1, originating from an acidophilic iron oxidizer, has been described as a promising candidate and is now explored for applied biocatalysis. Biological and synthetic nicotinamide cofactors were evaluated to fuel FOYE-1 to produce valuable compounds. A maximum activity of 319.7 ± 3.2 U mg-1 with NADPH or of 206.7 ± 3.4 U mg-1 with 1-benzyl-1,4-dihydronicotinamide (BNAH) for the reduction of N-methylmaleimide was observed at 30 °C. Especially, BNAH was found to be a promising reductant but exhibits poor solubility in water. Different organic solvents were assayed and FOYE-1 showed excellent performance in most systems with up to 20 vol% solvent and up to 40 °C. Purification and application strategies were evaluated on a small scale to optimize the process. Finally, a 200 mL biotransformation of 750 mg (R)-carvone afforded 495 mg of (2R,5R)-dihydrocarvone (>95% ee), demonstrating the simplicity to hand...

Source: Chembiochem - November 5, 2019 Category: Biochemistry Authors: Tischler D, Gädke E, Eggerichs D, Gomez Baraibar A, Mügge C, Scholtissek A, Paul CE Tags: Chembiochem Source Type: research