Engineering the Active Site of the Amine Transaminase from Vibrio fluvialis for the Asymmetric Synthesis of Aryl–Alkyl Amines and Amino Alcohols

Abstract Although the amine transaminase from Vibrio fluvialis has often been applied as a catalyst for the biocatalytic preparation of various chiral primary amines, it is not suitable for the transamination of α‐hydroxy ketones and aryl‐alkyl ketones bearing an alkyl substituent larger than a methyl group. We addressed this problem through a systematic mutagenesis study of active site residues to expand its substrate scope towards two bulky ketones. We identified two mutants (F85L/V153A and Y150F/V153A) showing 30‐fold increased activity in the conversion of ( S )‐phenylbutylamine and ( R )‐phenylglycinol, respectively. Notably, they facilitated asymmetric synthesis of these amines with excellent enantiomeric purities of 98 % ee .