Article

Immobilization of ω-transaminases by encapsulation in a sol-gel/celite matrix

Research Centre Applied Biocatalysis, c/o Department of Chemistry, Organic and Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria
Journal of Molecular Catalysis B Enzymatic (Impact Factor: 2.75). 04/2010; 63:39-44. DOI: 10.1016/j.molcatb.2009.12.001

ABSTRACT Commercially available ω-transaminases ω-TA-117, -113, and Vibrio fluvialis (Vf-AT) have been immobilized in a sol-gel matrix. Improved results were obtained by employing Celite 545 as additive. The immobilized ω-transaminases ω-TA-117, -113, and V. fluvialis (Vf-AT) were tested in the kinetic resolution of α-chiral primary amines. In contrast to the free enzyme ω-TA-117, the sol-gel/celite immobilized enzyme showed activity even at pH 11. Recycling of the sol-gel/Celite 545 immobilized ω-transaminase ω-TA-117 was performed over five reaction cycles without any substantial loss in enantioselectivity and conversion. Finally, the immobilized ω-TA 117 was employed in a one-pot two-step deracemization of rac-mexiletine and rac-4-phenyl-2-butylamine, two pharmacologically relevant amines. The corresponding optically pure (S)-amines were obtained in up to 95% isolated yield (>99% ee).

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