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An Aminotransferase from Enhydrobacter aerosaccus to Obtain Optically Pure ?-Phenylalanine.

ABSTRACT: An aminotransferase ?-TAEn was identified from Enhydrobacter aerosaccus. The ?-TAEn was successfully expressed in Escherichia coli and the obtained enzyme showed activity toward ?-phenylalanine (?-phe) at optimal conditions. For optically pure (R)-?-phe, 50% yield was observed by kinetic resolution of racemic amino with pyruvate as the amino acceptor. To obtain (S)-?-phe, the lipase/?-TAEn catalytic system was adopted. The ?-TAEn showed strict stereoselectivity to the amino donor. The formation of (S)-?-phe was observed using 3-aminobutyric acid as the amino donor, and (S)-?-phe was obtained by asymmetric synthesis with a yield of 82%.

SUBMITTER: Feng X

PROVIDER: S-EPMC7160847 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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An Aminotransferase from Enhydrobacter aerosaccus to Obtain Optically Pure β-Phenylalanine.

Feng Xinming X Guo Jing J Zhang Rubing R Liu Wei W Cao Yujin Y Xian Mo M Liu Huizhou H

ACS omega 20200402 14

An aminotransferase ω-TAEn was identified from Enhydrobacter aerosaccus. The ω-TAEn was successfully expressed in Escherichia coli and the obtained enzyme showed activity toward β-phenylalanine (β-phe) at optimal conditions. For optically pure (R)-β-phe, 50% yield was observed by kinetic resolution of racemic amino with pyruvate as the amino acceptor. To obtain (S)-β-phe, the lipase/ω-TAEn catalytic system was adopted. The ω-TAEn showed strict stereoselectivity to the ...[more]

PMID: 32309682

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