Synthesis of optically active amines employing recombinant ω-transaminases in E. coli cells

Abstract

Various recombinant ω-transaminases, overexpressed in E. coli cells and employed as whole-cell catalysts, are tested for the synthesis of enantiomerically pure amines from the corresponding prochiral ketones. Optically pure (S)-amines are obtained by formal reductive amination, consuming just ammonia and a cheap reducing agent (formate) with up to 99% ee and 97% yield. The other enantiomer was accessible by employing the same ω-transaminases in a kinetic resolution starting from racemic amines. A ω-transaminase derived from an Arthrobacter species displayed the highest stereoselectivity for all substrates tested, both for the kinetic resolution of rac-amines and for the amination of ketones. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.