Abstract：
:With the advantages of biocatalytic method, enzymes have been excavated for the synthesis of chiral amino acids by the reductive amination of ketones, offering a promising way of producing pharmaceutical intermediates. In this work, a robust phenylalanine dehydrogenase (PheDH) with wide substrate spectrum and high catalytic efficiency was constructed through rational design and active-site-targeted, site-specific mutagenesis by using the parent enzyme from Bacillus halodurans. Active sites with bonding substrate and amino acid residues surrounding the substrate binding pocket, 49L-50G-51G, 74M,77K, 122G-123T-124D-125M, 275N, 305L and 308V of the PheDH, were identified. Noticeably, the new mutant PheDH (E113D-N276L) showed approximately 6.06-fold increment of kcat/Km in the oxidative deamination and more than 1.58-fold in the reductive amination compared to that of the wide type. Meanwhile, the PheDHs exhibit high capacity of accepting benzylic and aliphatic ketone substrates. The broad specificity, high catalytic efficiency and selectivity, along with excellent thermal stability, render these broad-spectrum enzymes ideal targets for further development with potential diagnostic reagent and pharmaceutical compounds applications.
journal_name
J Microbiol Biotechnoljournal_title
Journal of microbiology and biotechnologyauthors
Jiang W,Wang Ydoi
10.4014/jmb.1907.07015subject
Has Abstractpub_date
2020-01-28 00:00:00pages
146-154issue
1eissn
1017-7825issn
1738-8872pii
10.4014/jmb.1907.07015journal_volume
30pub_type
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更新日期：2008-04-01 00:00:00
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更新日期：2010-12-01 00:00:00
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journal_title：Journal of microbiology and biotechnology
pub_type： 杂志文章,评审
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pub_type： 杂志文章,评审
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更新日期：2010-02-01 00:00:00
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pub_type： 杂志文章
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journal_title：Journal of microbiology and biotechnology
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更新日期：2008-02-01 00:00:00
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journal_title：Journal of microbiology and biotechnology
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journal_title：Journal of microbiology and biotechnology
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