Biocatalytic asymmetric amination of carbonyl functional groups - a synthetic biology approach to organic chemistry.

Transaminases catalyze amino transfer reactions from amino donors such as amino acids or amines to keto acids or ketones to give chiral amino acid or amines in optically pure form. alpha-Amino acid dehydrogenases catalyze the asymmetric reductive amination of alpha-keto acids using ammonia as amino donor to furnish L-amino acids. The distinct features and synthetic application of these two enzymes are reviewed in an effort to illustrate their promising and challenging aspects in serving as approaches to the direct asymmetric synthesis of optically pure amines from the corresponding keto compounds, a formidable problem in organic chemistry.