Asymmetric Synthesis of (R)-3-fluoroalanine from 3-fluoropyruvate Using Omega-transaminase

• Published in: Biotechnology and bioprocess engineering 2011, 16(2), , pp.291-296
• Main Authors: Bea, H.S., Yeungnam University, Gyeongsan, Republic of Korea, Lee, S.H., Catholic University of Daegu, Gyungsan, Republic of Korea, Yun, H.D., Yeungnam University, Gyeongsan, Republic of Korea
• Format: Article
• Language: English
• Subjects: (R)-3-fluoroalanine; 3-fluoropyruvate; Acetophenone; ACIDE AMINE; Amines; AMINO ACIDS; AMINOACIDOS; Asymmetric synthesis; Biosynthesis; Biotechnology; Chemistry; Chemistry and Materials Science; chiral amines; Dehydrogenases; E coli; Enzymes; Industrial and Production Engineering; Kinetics; Membrane reactors; Microorganisms; omega-transaminase; Oxidation; pH effects; Phosphate; Proteins; Research Paper; Studies; unnatural amino acid; Vibrio fluvialis; 생물공학
• ISSN: 1226-8372; 1976-3816
• DOI: 10.1007/s12257-010-0282-x

In this study, (R)-3-fluoroalanine was asymmetrically synthesized from 3-fluoropyruvate (F-pyruvate) and (S)-α-methylbenzylamine (MBA) using recombinant ω-transaminase (TA) from Vibrio fluvialis JS17. The reaction was severely inhibited by acetophenone (deaminated product of α-MBA). In the presence of 5 mM acetophenone, the reactivity of the enzyme towards F-pyruvate decreased by 78%. To overcome the product inhibition by acetophenone, a biphasic reaction was successfully used. The conversion of F-pyruvate into (R)-3-fluoroalanine (enatiomeric exess (e.e.) greater than 99%) was about 95% in the biphasic system (75 mM F-pyruvate, 100 mM (S)-α-MBA, and 3.0 U/mL), whereas 31% was obtained without product extraction. The use of racemic α-MBA as an amino donor instead of (S)-α-MBA can reduce the reaction cost and also produce chiral amines through kinetic resolution. When the kinetic resolution of racemic α-MBA (40 mM) was carried out with F-pyruvate (30 mM) and ω-TA (3.0 U/mL) in 100 mM phosphate buffer (pH 7.0), the e.e. of (R)-α-MBA reached 98.4% with 52.2% conversion for 10 h and 21 mM (R)-3-fluoroalanine was produced with 70% conversion and an e.e. greater than 99%.