Recent Advances in Protein Engineering and Synthetic Applications of Amino Acid Transaminases

Amino acid transaminases (ATs) have garnered considerable attention in recent years as promising biocatalysts for the synthesis of high‐value chiral chemicals, including both natural and non‐canonical amino acids. These enzymes catalyze the transfer of amino groups from amino acids to keto acids, playing a pivotal role in various biological processes and industrial applications. Characterized by their high turnover rates, remarkable enantioselectivity, and broad substrate specificity, ATs exhibit exceptional versatility and potential. This review presents a comprehensive overview of the classification, reaction mechanisms, and activity assays of ATs. More crucially, we delve into the recent advancements in protein engineering of ATs through directed evolution and rational/semi‐rational design strategies, which have been instrumental in addressing limitations such as low catalytic efficiency and stability. Furthermore, we survey the recent synthetic applications of ATs in the production of aliphatic and aromatic amino acids, highlighting smart amino donors and coupling methods that effectively shift the equilibrium of transamination reactions, as well as enzyme cascades that further expand the scope of reactions. By bridging gaps in research on ATs, this review aims to provide valuable insights and guide for future developments in the field of biocatalysis, ultimately fostering their continued utilization and advancement.