ω-Transaminase(S-/R-)

ω‑Transaminases (S‑type/R‑type) are PLP‑dependent enzymes that transfer an amino group from a donor to a ketone or aldehyde under mild conditions, producing chiral amines. Their (S)‑ or (R)‑stereoselectivity allows the selective synthesis of the corresponding (S)‑ or (R)‑amine, and they are employed industrially for large‑scale production of chiral amine building blocks. Representative applications include the use of an (R)‑ω‑TA (ATA‑117) to synthesize the antidiabetic drug sitagliptin with markedly improved yield and optical purity; an (S)‑ω‑TA applied in a two‑phase system to efficiently produce (R)‑1‑(5‑fluoropyrimidin‑2‑yl)ethylamine, a key intermediate for a JAK2 inhibitor; patented site‑directed mutants with high activity used to synthesize (S)‑1‑benzyloxycarbonyl‑3‑aminopyrrolidine and (S)‑1‑benzyloxycarbonyl‑3‑aminopiperidine, dramatically reducing enzyme loading and cost; and the use of ω‑TAs in continuous‑flow or immobilized setups to generate γ‑amino acids and their bioactive peptide precursors, meeting the demand for chiral intermediates in fine chemicals and agrochemicals. Owing to their high stereoselectivity, green processing, and engineerable stability, ω‑transaminases have become core biocatalysts for producing chiral amines in the pharmaceutical, fine‑chemical, fragrance, and pesticide industries.