Comparison of the omega-transaminases from different microorganisms and application to production of chiral amines

Biosci Biotechnol Biochem. 2001 Aug;65(8):1782-8. doi: 10.1271/bbb.65.1782.

Abstract

Microorganisms that are capable of (S)-enantioselective transamination of chiral amines were isolated from soil samples by selective enrichment using (S)-alpha-methyl-benzylamine ((S)-alpha-MBA) as a sole nitrogen source. Among them, Klebsiella pneumoniae JS2F, Bacillus thuringiensis JS64, and Vibrio fluvialis JS17 showed good omega-transaminase (omega-TA) activities and the properties of the omega-TAs were investigated. The induction level of the enzyme was strongly dependent on the nitrogen source for the strains, except for V. fluvialis JS17. All the omega-TAs showed high enantioselectivity (E>50) toward (S)-alpha-MBA and broad amino donor specificities for arylic and aliphatic chiral amines. Besides pyruvate, aldehydes such as propionaldehyde and butyraldehyde showed good amino acceptor reactivities. All the omega-TAs showed substrate inhibition by (S)-alpha-MBA above 200 mm. Moreover, substrate inhibition by pyruvate above 10 mm was observed for omega-TA from V. fluvialis JS17. In the case of product inhibition, acetophenone showed much greater inhibitions than L-alanine for all omega-TAs. Comparison of the enzyme properties indicates that omega-transaminase from V. fluvialis JS17 is the best one for both kinetic resolution and asymmetric synthesis to produce enantiomerically pure chiral amines. Kinetic resolution of sec-butylamine (20 mM) was done under reduced pressure (150 Torr) to selectively remove an inhibitory product (2-butanone) using the enzyme from V. fluvialis JS17. Enantiomeric excess of (R)-sec-butylamine reached 94.7% after 12 h of reaction.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amines / chemical synthesis*
  • Bacillus thuringiensis / enzymology
  • Butylamines / chemistry
  • Dialysis
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology
  • Kinetics
  • Klebsiella pneumoniae / enzymology
  • Molecular Conformation
  • Soil Microbiology
  • Stereoisomerism
  • Substrate Specificity
  • Transaminases / antagonists & inhibitors
  • Transaminases / chemistry*
  • Vibrio / enzymology
  • beta-Alanine-Pyruvate Transaminase

Substances

  • Amines
  • Butylamines
  • Enzyme Inhibitors
  • Transaminases
  • beta-Alanine-Pyruvate Transaminase